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INTRODUCTION

2. Research purposes This study generally focuses on analyzing the impact of credit risk

1. The necessary of the study Credit risk affects the bank’s prosperity and sustainability by

on profitability at Vietnam joint stock commercial banks. Specifically:

influencing its profitability. There are many studies looking at the

(i) considering the impact of credit risk arising from on-balance-sheet

effect of credit risk on bank profitability, however, these studies only

and off-balance sheet activities at Vietnam joint stock commercial

employed on-balance sheet credit risk measures (arising from loans)

banks; (ii) considering the impact of credit risk on ROA, ROE in

without paying much attention to the credit risk of off-balance sheet

Vietnam joint stock commercial banks in the period 2009-2018 as a

items. The conclusions from these studies are still inconsistent, that

linear or non-linear relationship; (iii) considering the impact of credit

credit risk may have positive or negative effects on ROA, ROE, and

risk on profitability in Vietnam joint stock commercial banks with

positive effects on NIM. Meanwhile, the theoretical basis and current

differences in the size of total assets; (iv) proposing recommendations

situations in Vietnam show that the impact of the credit risk on bank

derived from research results to limit credit risks and promote

profitability may be a non-linear relationship.

profitability at Vietnamese joint stock commercial banks.

In recent years, the bad debt ratio in Vietnam commercial banks

The author has proposed the following research questions:

has increased sharply, eroding their profit before tax due to the

i) How does credit risk arising from on- and off-balance sheet

provision of credit risk reserve. Besides, the proportion of off-balance

activities affect the bank profitability at Vietnam joint stock

sheet items to total on-balance-sheet assets has tended to increase in

commercial banks?

recent years. Changing the credit risk provisioning for off-balance

ii) Is the impact of credit risk on profitability ratios (ROA, ROE)

sheet items since 2014 can also have negative long-term effects,

at Vietnam joint stock commercial banks in the period 2009-2018 is a

especially in a developing economy like Vietnam. With the

non-linear relationship?

restructuring roadmap, in the coming time, Vietnamese commercial

iii) Is the impact of credit risk on profitability ratios at Vietnam

banks must increase their capital to meet capital safety conditions.

joint stock commercial banks different by asset size?

Therefore, the effect of total assets size on the impact of credit risk on

3. Subjects and scope of research  Research subjects: The impact of credit risk on profitability in

bank profitability should also be considered.

Vietnam joint stock commercial banks.

Thus, it can be seen that the research on the impact of credit risk

on bank profitability is an objective requirement from practice in

 Research scope: + Space: 31 Vietnam joint stock commercial banks.

Vietnam. Therefore, the topic “The impact of credit risks on the

profitability at Vietnam joint stock commercial banks” is selected for

+ Time: from 2009 to 2018. 4. Methodology

this desertation.

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 Aprroach:

sheet activities has a negative impact on ROA and ROE, so the risks

+ The thesis uses a combination of traditional profitability ratios in the

from these activities need more attention in the long term, especially

banking sector (ROA, ROE, NIM), and at the same time uses the

in the context of off-balance sheet activities and the derivative stock

measure of credit risk arising from both on- and off-balance sheet

market in Vietnam is developing day by day.

activities which hoping to bring about the most consistent estimation.

Secondly, the thesis provides for the first time empirical evidence

+ Research data is presented as unbalanced table data for the period

of the non-linear impact of credit risk on ROA and ROE at Vietnam

from 2009 to 2018. Data on bank characteristics and microeconomics

joint stock commercial banks. This result shows that low/moderate

are collected and calculated from database of Vietstock, World Bank

credit risk will boost commercial banks’ profitability, but if credit risk

and the State Bank of Vietnam.

rises above the optimal threshold, its increase will decline profitability

+ The thesis builds a research model on the impact of credit

due to the erosion of the risk provision for operating profits as well as

rireprodbank profitability as well as the factors that influence this

financial losses when the customer violates the obligation to repay.

relationship such as the ratio of loan to total assets, capital structure,

Thirdly, the thesis examines the effect of the total assets on the

income diversification, cost effectiveness, total assets, market

impact of credit risk on bank profitability,

thereby giving

concentration, economic growth and inflation. Besides, the thesis uses

recommendations and policy implications close to reality.

6. Desertation structure

dummy variables and interactive variables related to the total assets to

clarify research objectives.

The thesis is presented in five chapters:

Chapter 1. Literature review.

 Methodology The thesis employs the two-step system GMM estimation method

Chapter 2. Theoretical framework.

to examine the impact of credit risk on bank profitability in order to

Chapter 3. Methodology.

handle endogenous problems and potential defects, allowing to

Chapter 4. Research results.

Chapter 5. Conclusions and recommendations.

generate exactly estimated results.

5. New contributions of the research Although the impact of credit risk on bank profitability is a

traditional topic and has been concerned by many researchers, this

thesis still has some new contributions as follows:

First, this can be seen as a pioneering study in the use of credit risk

provision to measure credit risk arising from off-balance sheet

activities at Vietnam commercial banks. Credit risk from off-balance

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1.1.4. The non-linear impact of credit risk on ROA, ROE

CHAPTER 1: LITERATURE REVIEW

Previous studies show that the effect of risk on returns can be non-

linear, specifically: during periods of low or medium volatility, the

1.1. Overview of research works related to the topic 1.1.1. The impact of on-balance sheet credit risk on ROA, ROE

trade-off relationship between risk (due to volatility market) and the

With the bank profitability measured by ROA, ROE and on-

expected return is positive; on the contrary, during periods of strong

balance sheet credit risk measured by non-performing loans ratio or

market volatility, this relationship is inverse. However, to the extent

loan loss provisions ratio, most previous studies have shown a

of the author’s understanding, the empirical evidence on the non-linear

negative impact of credit risk on ROA, ROE. However, with the same

impact of credit risk on banks’ profit has not yet been studied,

measures as above, others show that the impact between these two

especially at Vietnamese commercial banks.

variables is in a positive direction, especially research in developing

1.1.5. Estimation methods

countries such as Ghana, Tunisia, Bangladesh, MENA, China.

Perivious studies have used different estimation methods such as:

1.1.2. The impact of on-balance sheet credit risk on NIM

Ordinary Least Squares (OLS), Fixed Effects Model (FEM), Random

With the bank profitability measured by NIM, most studies have

Effects Model (REM), General Method of Moments (GMM). In

shown the positive effect of credit risk (measured by non-performing

particular, GMM is still considered as the optimal method to deal with

loans ratio and loan loss provisions ratio) on the dependent variable.

the potential defects of the research model, providing more efficient

1.1.3. The impact of off-balance sheet credit risk on bank

and accurate estimation results.

profitability

1.2. Research gaps

Previous studies show that off-balance sheet transactions are

First, credit risk measurements are commonly used in previous

associated with bank risks and negatively impact on bank profitability.

studies including the non-performing loans ratio and loan loss

When these transactions increase, risks will arise due to the moral

provisions ratio. However, credit risk arising from off-balance sheet

hazard effect and the negative long-term impact of off-balance sheet

items has not been considered and interested, especially studies in

activities on bank profitability should be paid more attention. Research

Vietnam. Therefore, the author proposes to make provision for credit

overview in Vietnam shows that studies on off-balance sheet activities

risk arising from off-balance sheet items even when there are no

are still very limited. To the author’s best of knowledge, up to now,

obligations to fulfill banks’ commitments. With the expectation that

there have been no studies in Vietnam that have proposed a specific

credit risk will be considered more comprehensively, this thesis will

measurement to measure credit risk arising from off-balance sheet

include both on- and off-balance sheet credit risk. Up to now, in

activities.

Vietnam, there is no research to mention the provision for credit risk

arising from off-balance sheet items.

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Second, some studies have shown the relationship between risk and

income against revenue, operating costs, assets and shareholder equity

return is a non-linear relationship in an inverted U-shape. On the other

at a specifically time.

hand, through an overview of the theoretical basis and the situation of

2.1.2. The indicators reflect the bank profitability  Returns on Average Total Assets (ROA)

bad debt and bank profitability in Vietnamese, the author suspects that

The rate of return on average total assets is an indicator reflecting the

there may exist a nonlinear U-shaped relationship between the credit

level of profit that a bank can receive over its assets, a measurement

risk and ROA, ROE at Vietnamese commercial banks in the research

of the managing efficiency and using assets to generate income.

period. Therefore, this study can be considered as a pioneer in

Profit after tax

providing empirical evidence of the non-linear effect between credit

ROA =

risk and bank profitability (ROA, ROE) in Vietnam.

Average Total Assets

Third, the Vietnamese banking sector is undergoing restructuring

 Returns on Average Equity (ROE)

with a series of mergers between banks, leading to the formation of

Return on average equity reflects the income that shareholders or

larger banks. Increasing the total assets can have a positive impact on

investors can get on the money they have spent.

a bank’s profitability, but also may reduce the bank’s performance due

Profit after tax

ROE =

to management reasons, office costs. However, up to now, there has

Average Equity

been no study comparing the impact of credit risk on bank profitability

 Net Interest Margin (NIM)

by groups of banks with differences in total assets size. Therefore, this

The net interest margin is the difference between the bank’s interest

study will contribute to clarifying the impact of the total assets on the

income and its cost of interest payments over its average interest

impact of credit risk on profitability at Vietnam joint stock commercial

earning assets, representing the actual income the bank receives from

banks in order to make policy implications consistent with reality.

the difference between loans and capital mobilization interest rates.

Net interest income

NIM =

CHAPTER 2: THEORETICAL FRAMEWORK

Average Total interest assets

2.1. The bank profitability

 Risk-adjusted rates of return

2.1.1. The concept of profitability

Risk-adjusted return on capitals (RAROC), risk-adjusted return on

According to Rose (1999), the profitability is the ratio of net

total assets (RAROA) and risk-adjusted return on equity (RAROE).

income after tax to total assets or equity. Profitability ratio is a group

2.2. Credit risk of commercial banks

of financial indicators used to evaluate a bank’s ability to generate

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2.2.1. Credit risk concept

In principle, the purpose of loan loss provisions is to adjust the provision

The Basel Committee on Banking Supervision (Basel, 2000)

for losses to reflect expected future losses in the bank’s loan portfolio.

Loan loss provisions

defined “credit risk is the ability to lose part or all of the value of a

LLP =

loan due to credit problems such as the borrower violation of debt

Total loans

repayment obligations, divestment or delay in repayment, or change

 Off-balance sheet credit risk

in loan interest rate”.

There are many studies on the risks of off-balance sheet activities, but

Commercial banks increasingly face credit risk not only in lending

these studies do not separate credit risk and consider the overall risks

activities but also in many other activities. Although there is no

brought about by these activities. Therefore, the author will propose

specific concept of the credit risk of off-balance sheet activities, the

off-balance sheet credit risk measurement in the next chapter.

Bank for International Settlements (BIS) has emphasized that the risks

 Others

of off-balance sheet transactions, especially credit risks, there is no

Net Charge-Offs (NCO), Standard deviation of Net Interest Margin.

difference from on-balance sheet activities and should be analyzed in

2.3. Other determinants of the bank profitability

the same way as credit risk of on-balance sheet activities (BIS, 1986).

2.3.1. The bank characteristics

Credit risk arising from off-balance sheet activities can be

understood as unexpected losses that banks can suffer when

partners/customers default or breach committed obligations due to

changes in financial capacity in the process of engaging in off-balance

sheet transactions. When customers default, the bank must fulfill its

 The loans to total assets ratio  Capitalization  Cost efficiency  Income diversification  Total assets

commitments, that is, convert these off-balance sheet activities into

on-balance-sheet loans.

2.2.2. Credit risk measurement indicators  Non-performing loans ratio (NPL)

This indicator directly reflects the credit risk situation of the bank, and

2.3.2. Macroeconomics factors  Industry concentration  Inflation  Economic growth 2.4. Foundational theories

at the same time shows the size and the rate of difficult-to-recover

2.4.1. Risk-Return Trade-off Theory

capital in the bank’s loan portfolio.

First mentioned by Markowitz (1952) and further confirmed by

Non-performing loans

Sharpe (1964), Lintner (1965) and Merton (1973). Accordingly, the

NPL =

Total Loans

higher the risk of an asset/investment portfolio, the greater the return that

 Loan loss provisions ratio (LLP)

investors expect to achieve. However, Whitelaw (2000), Rossi &

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Timmermann (2010), Ghysels et al. (2013), Aragó & Salvador (2013)

agree with the view of the non-linear impact of risk on return: in the period

of low or medium volatility in the market, the relationship between

market volatility risk and expected return is positive; by contrast, during

periods of strong market volatility, this relationship is inverse.

2.4.2. Information Asymmetry Theory

First mentioned by the “lemons” hypothesis of Akerlof (1970),

Stiglitz & Weiss (1981) developed this theory through two effects,

adverse selection and moral hazard. According to both effects

mentioned above, lending interest rates affect credit risk and

profitability of banks: increasing lending interest rate means that credit

Figure 2.1. Research model framework

risk of the loan portfolio also increases, leading to reducing

Source: Author

profitability of the bank. Stiglitz & Weiss (1981) also shows that when

the lending interest rate reaches a certain level of r*, the bank’s profit

CHAPTER 3: METHODOLOGY

is maximum. On the other hand, if the bank increases the interest rate

3.1. Research model

beyond a certain r*, it increases the risk of the loan and therefore

3.1.1. Choice of dependent variables

reduces the bank’s profit.

The thesis employs three measurements of bank profitability,

2.4.3. Other hypothesis

namely ROA, ROE, NIM.

Berger & DeYoung (1997) developed hypotheses such as: Bad

3.1.2. Choice of independent variables

luck hypothesis, Bad management hypothesis, Skimping hypothesis,

The thesis uses two measurements, namely On-balance-sheet

Moral Hazard hypothesis.

credit risk provision and Off-balance sheet credit risk provision ratio.

2.5. Research theoretical framework

3.1.3. Choice of control variables

On the basis of research overview and theoretical basis, the author

Including bank-specific variables and macroeconomic variables.

constructs the research theoretical framework presented in Figure 2.1.

The variables used are summarized in the table below:

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Table 3.1. Explain the variables in the research model

Where:

Variables Measurement

+ Y are the dependent variables measuring bank profitability,

Expected sign

including ROA, ROE, NIM

+ X are independent variables measuring credit risk, including LLP

and OBS

Bank profitability ROA ROE NIM

+ Ctr are control variables, including variables belonging to the bank

Profit after tax/Average Total Assets Profit after tax/Average Equity Net interest income/Average Total interest assets

characteristics and the macro environment.

Credit risk LLP +/–

+ The parameter p is the ordinal number of the credit risk and control

variables (p є [1,k]), i represents the i bank and t represents the year t.

OBS +/– Provision for on-balance sheet credit risk /Total loans Provision for off-balance sheet credit risk /Total off-balance sheet items

3.2. Research data

3.2.1. Source of data

Total loans/Total Assets +

Data on bank characteristics are collected and calculated from

annual reports and audited financial statements of 31 joint stock

+/– –

commercial banks in Vietnam. Macro-environment data is collected

from the World Bank database.

3.2.2. Description of research data

+/- +/– +/– Bank characteristics LA (Loans to Assets ratio) ETA (Capital Structure) HHI (Income Diversification) COST (Cost Efficiency) LNTA (Bank size) SIZEdum (Dummy variable on the size of total assets)

3.2.2.1. Descriptive statistics of the study sample

Equity/ Total Assets (Interest income/Total income)2 + (Non-interest income/Total income)2 Operating expenses/Total Assets Natural logarithm of total assets Equal to 1 if total assets are more than VND 100,000 billion; equal to 0 for the remaining cases

Table 3.2. Descriptive statistics of variables

Variable Number of Mean Median Standard Min Max + observations deviation Macroeconomic CR3 (Industry concentration) INF (Inflation) +/– ROA 298 0,8359 0,7148 0,6053 0,053 2,4476 ROE 298 9,1525 8,03 6,8802 0,2019 27,493 GDP (Economic growth) rate of gross domestic + The assets proportion of three largest commercial banks Growth rate of consumer price index (CPI) Growth product NIM 298 2,7598 2,7174 1,0530 0,5466 5,255

Source: Author

LLP 298 1,2641 1,152 0,4568 0,2402 2,3166

3.1.4. Research models

OBS 298 0,7288 0,75 0,2534 0,1015 1,1857

Based on research overview of domestic and foreign authors, the

LA 298 0,5412 0,5546 0,1232 0,3134 0,8163

research model of the desertation has the following form:

ETA 298 9,6218 8,71 3,8090 3,2572 17,915

Yi,t = α + Σβp (Xit + Ctrit) + εit

HHI 297 0,7207 0,7101 0,1365 0,5001 0,9596

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COST 297 1,5750 1,554 0,4693 0,369 2,689

CHAPTER 4: RESEARCH RESULTS

LNTA 298 18,189 18,202 1,1570 15,018 20,995

4.1. Situation of Vietnam’s commercial banking system

CR3 310 40,845 40,472 4,9183 31,663 50,498

The thesis has presented an overview of the size and number of

INF 310 6,138 5,651 3,5960 0,879 13,885

banks, income structure, off-balance sheet activities as well as the

GDP 310 6,1492 6,2255 0,6010 5,247 7,076

reality of credit risks and profitability rates in the period 2009-2018.

4.2. Research results

Source: Stata

4.1.1. Linear impact of credit risk on profitability

3.2.2.2. Correlation coefficient matrix

Table 4.3. Estimation results of the model of linear impact of

The correlation coefficient matrix between the explanatory

credit risk on profitability

variables shows that most of the correlation coefficients are below 0,5,

Dependent

showing that there is no close correlation between the pairs of

ROA ROE NIM variables

explanatory variables. Multicollinearity may occur between LNTA

and ETA variables (73.2%).

Models (1) (2) (3) (4) (5) (6)

3.2.3. Check the robustness of research data

ROAt-1 0,5710*** 0,6096***

The tests show that the models have a suitable format. However, the

ROEt-1 0,7272*** 0,5571***

models may experience multicollinearity (mean value of VIF is

NIMt-1 0,2197*** 0,2564***

greater than 2.5), heteroscedasticity (occurs in all models) and series

LLP -0,1588*** -2,0919*** 0,2827**

autocorrelation (occurs in all models).

OBS -1,0218*** -19,702*** -0,1681

3.3. Estimation method

LA 0,5407* 0,5653*** 0,7642 9,9667*** 3,1069*** 1,4375***

For reliable research results, the author will use two-step system

ETA 0,0186** 0,0158* 0,1558** -0,1098 -0,0461* -0,0550***

generalized moment estimation method (2-step System Generalized

HHI -2,3520*** -1,8135*** -23,143*** -15,897*** 1,9147*** 0,7164**

Method of Moments - 2-step SGMM). Besides, the thesis uses tests

COST 0,0979* 0,0874* 0,9176* 1,6723** 0,9458*** 1,1969***

such as Sargan, Hansen, Arellano–Bond to check the appropriateness

LNTA 0,0082 0,0100 0,3256 0,3834 -0,2035*** -0,1284***

of the estimation method.

CR3 -0,0041** -0,0041* -0,0805*** -0,0561*** 0,0105*** 0,0135***

Since the estimation method is GMM, the research model will be

INF 0,0489*** 0,0396*** 0,2554*** 0,3475*** 0,0760*** 0,0977***

adjusted as follows:

GDP 0,2171*** 0,2446*** 2,3265*** 2,6061*** 0,0763 0,1133***

Yi,t = α + δYi,t-1 + Σβp (Xit + Ctrit) + εit

No. groups 31 31 31 31 31 31

Where Yi,t-1 is the 1-period lag variable of the dependent variables.

No. Instr. 29 29 30 28 30 30

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F-test No. groups 0,000 0,000 0,000 0,000 0,000 0,000 31 31 31 31 Sargan test No. Instruments 0,103 0,260 0,985 0,779 0,090 0,836 30 29 31 31 Hansen test F-test 0,491 0,409 0,702 0,588 0,285 0,196 0,000 0,000 0,000 0,000 AR(1) Sargan test 0,000 0,001 0,004 0,001 0,042 0,006 0,980 0,272 0,886 0,985 AR(2) Hansen test 0,608 0,883 0,207 0,624 0,987 0,577 0,695 0,489 0,887 0,740 AR(1) Note: (*), (**), (***) are at 10%, 5% and 1% significance level respectively. 0,016 0,005 0,007 0,004

Source: STATA

AR(2) 0,611 0,452 0,152 0,299

4.1.2. Non-linear impact of credit risk on profitability

Note: (*), (**), (***) are at 10%, 5% and 1% significance level respectively.

Table 4.4. Model estimation results of non-linear impact of credit

Source: STATA

risk on ROA, ROE

4.1.3. The impact of credit risk on the profitability ratio of the bank’s

Dependent variables ROA ROE

total assets

(7) (8) (9) (10) Models

Table 4.5. Estimation results of the model of the effect of total asset

size on the impact of credit risk on profitability

ROAt-1 0,5326*** 0,5423***

Dependent variables

ROA ROE NIM ROEt-1 0,7759*** 1,0391*** Models (11) (12) (13) (14) (15) (16) NIMt-1 ROAt-1 0,4879*** 0,5144*** LLP 1,0837*** 10,824*** ROEt-1 0,6025*** 0,6119*** LLP2 -0,3780*** -3,6386*** NIMt-1 0,1982*** 0,1734*** OBS 0,9055* 19,218** LLP -0,5093*** -2,6987*** -0,0836 OBS2 -0,7425** -14,895** OBS -1,8849*** -16,129*** -0,7464 LA -0,6241 0,6587*** 0,5355 5,5390** LA 0,0483 0,3749* 5,9682** 7,8637** -0,1051 0,9043 ETA -0,0480*** -0,0229*** -0,2343*** -0,3381*** ETA 0,0666*** 0,0656*** -0,2014 0,4754** 0,0159 0,0166 HHI -0,8662** -1,2275*** -9,2917*** -9,9908*** HHI -1,9174*** -1,5862*** -14,943*** -18,388*** 0,9623*** 1,4526*** COST 0,3070*** 0,1385* 1,0645* 1,4523** COST 0,0940* 0,0402 1,9661** -0,3255 0,8584*** 0,5313*** LNTA -0,0151 -0,0325** -0,6034*** -0,7220*** CR3 -0,0070*** -0,0039* -0,0486** -0,0526** 0,0057** 0,0080** CR3 -0,0001 -0,0009 -0,0958*** -0,0700*** INF 0,0472*** 0,0438*** 0,3653*** 0,3155** 0,0589*** 0,0806*** INF 0,0310** 0,0531*** 0,0732 0,2095** GDP 0,2380*** 0,2876*** 2,0219*** 3,1492*** -0,0732 -0,1195 GDP 0,0977** 0,1541*** 2,5507*** 2,3160***

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SIZEdum

Fifth, the estimated results show a positive correlation between cost

-0,2870* -0,8697*** -3,3582*** -5,3465** 0,3923 1,4842

effectiveness and dependent variables.

SIZEdum*LLP 0,4608*** 2,9785*** -0,1845

Sixth, the size of total assets (measured by LNTA and SIZEdum) is

SIZEdum*OBS 1,5426*** 11,176*** -1,4404

negatively correlated with the dependent variables.

No. groups 31 31 31 31 31 31

Seventh, industry concentration is negatively related to ROA and

No. Instruments 30 30 30 30 30 30

ROE, and positively related to NIM.

F-test 0,000 0,000 0,000 0,000 0,000 0,000

Eighthly, inflation has a positive impact on the profitability of

Sargan test 0,474 0,233 0,940 0,885 0,002 0,353

Vietnamese commercial banks.

Hansen test 0,496 0,533 0,418 0,603 0,142 0,447

Ninth, economic growth is the driving force for profit growth of

AR(1) 0,009 0,001 0,002 0,001 0,049 0,008

Vietnamese commercial banks.

AR(2) 0,101 0,531 0,868 0,201 0,808 0,538

Tenth, the impact of credit risk on profitability (ROA, ROE) at

Vietnamese joint stock commercial banks is non-linear in the shape of

Note: (*), (**), (***) are at 10%, 5% and 1% significance level respectively. Source: STATA

an inverted U (bell shape), which means that credit risk at a

4.3. Discussing research results

low/moderate level will promote growth rate of return, but if credit

4.3.1. Interpretation of estimated results

risk increases and exceeds a certain threshold, it will reduce

Firstly, on-balance sheet and off-balance sheet credit risk are

profitability due to losses from high-risk loans.

negatively correlated with bank’s ROA and ROE, that is, the higher

Eleventh, the interaction variable between SIZEdum and credit risk

the credit risk, the lower the bank’s profitability. The estimation

variables has a positive correlation with ROA, ROE and is not

results also show that on-balance sheet credit risk has a positive effect

statistically significant with NIM, demonstrating the adverse impact

on NIM, while off-balance sheet credit risk does not find a statistically

of credit risk on return rates (ROA, ROE) at commercial banks with

significant effect on NIM.

slightly decreasing trend in banks with large asset size compared to

Second, the ratio of total loans to total assets has a positive impact on

banks with small asset size (with the same credit risk and other

the profitability of Vietnamese joint stock commercial banks.

conditions).

Third, capital structure can have a positive or negative effect on ROA

4.3.2. Answering research questions

and ROE and have a negative impact on NIM.

Fourth, income diversification has a positive effect on the increase of

 Research question 1: Both on-balance sheet and off-balance sheet credit risk have a negative impact on ROA and ROE. On-balance

ROA and ROE, but decreases the NIM.

sheet credit risk has a positive impact on NIM but no impact on NIM

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– – k

(no statistical significance) at Vietnamese joint stock commercial

banks during the research period from 2009-2018.

Dummy variable on the size of total assets (SIZEdum) Interaction variable (SIZEdum*LLP) Interaction variable (SIZEdum*OBS) + + + + k k

Source: Author

 Research question 2: The impact of credit risk on profitability (ROA, ROE) at Vietnamese joint stock commercial banks in the

Note: k: not statistically significant; n/a: do not run the model

period 2009-2018 is a non-linear effect in an inverted U shape, which

5.2. Recommendations for commercial banks

means that credit risk is at a low/moderate level will boost return

5.2.1. Building a credit risk management model focusing on off-

growth, but if credit risk rises and crosses a certain threshold, it will

balance sheet activities

reduce profitability due to losses from high-risk loans.

5.2.2. Accelerating loan growth

5.2.3. Building a reasonable capital structure

 Research question 3: The negative impact of credit risk on profitability (ROA, ROE) in banks with large assets will tend to

5.2.4. Diversify non-credit activities

decrease slightly compared to banks with small assets (with the same

5.2.5. Estimate the optimal level of credit risk

credit risk and other conditions). This study did not find evidence that

5.2.6. Some other recommendations

the impact of credit risks on NIM was different by the total asset size.

5.3. Recommendations for the Government, the State Bank

CHAPTER 5: CONCLUSIONS AND RECOMMENDATIONS

5.4. Dissertation contributions

Firstly, the thesis once again confirms the negative impact of credit

5.1. Conclusions

risk on ROA, ROE and positive impact on NIM. Besides, this can be

Table 5.1. Summary of the results

considered as a pioneering study in measuring credit risk arising from

off-balance sheet activities by the ratio of credit risk provision for off-

ROA – +, – ROE – +, – NIM + n/a

balance sheet activities in Vietnam.

Secondly, for the first time, the thesis provides empirical evidence on

– +, – – +, – k n/a

the non-linear impact of credit risk on profitability (ROA, ROE) at

Vietnamese joint stock commercial banks in the period 2009-2018.

This result proves that low/moderate credit risk will promote the

increase in profitability of commercial banks, but if the increase in

credit risk exceeds the optimal threshold, its increase will decrease the

profitability due to the erosion of provisions to operating profit as well

Dependent Variables On-balance sheet credit risk (LLP) Non-linear impact of on-balance sheet credit risk (LLP – LLP2) Off-balance sheet credit risk (OBS) Non-linear impact of off-balance sheet credit risk (OBS – OBS2) Loans to total assets (LA) Capital Structure (ETA) Income Diversification (HHI) Cost Efficiency (COST) Bank size (LNTA) Industry Concentration (CR3) Inflation (INF) Economic Growth (GDP) + +/– – + – – + + + +/– – + – – + + + – + + – + + +

as financial weakness of commercial banks.

24

23

LIST OF RESEARCH WORKS OF THE AUTHOR

Third, the thesis examines the influence of asset size on the impact of

credit risk on the dependent variable, the results show that the negative

impact of credit risk on ROA and ROE at banks with large total assets

will be slightly lower than that of small-sized banks (with the same

credit risk and other conditions). This study has not found the effect

of total asset size on the impact of credit risk on NIM.

Fourth, the thesis has used a combination of control variables

belonging to the characteristics of the bank and macroeconomic

factors. The estimated results will be the basis for providing solutions

and policy implications close to reality, as a reference for managers.

5.5. Dissertation limitations

Firstly, this study only focuses on traditional returns such as ROA,

ROE and NIM, whether not mentioning non-interest margin (NNIM),

risk-adjusted returns due to limited data sources.

Second, this thesis has not provided the optimal point/inflection

point in the model of non-linear effects of credit risk on ROA, ROE

because each bank has its own characteristics, different risk appetite,

cannot be determined a common optimum for all banks.

Thirdly, the research scope of the thesis is a country, and has not

mentioned state-owned, joint-venture and foreign banks, so it is not

possible to compare the impact of credit risk on profitability according

to the difference between countries or forms of ownership.

Fourth, the factors belonging to the characteristics of banks are still

RELATED TO DESERTATION 1. Dieu Thi Thanh Tran & Ha Thi Thu Phan (2020), Bank Size, Credit Risk and Bank Profitability in Vietnam, Malaysian Journal of Economic Studies 57(2): 233–251. doi: 10.22452/MJES.vol57no2.4 2. Phan Thị Thu Hà & Trần Thị Thanh Diệu (2020), Tác động của rủi ro tín dụng đến tỷ suất sinh lời tại các ngân hàng thương mại cổ phần Việt Nam có hoạt động sáp nhập, Tạp chí Kinh tế & Phát triển, Số 277, trang 24-34 3. Phan Thị Thu Hà & Trần Thị Thanh Diệu (2020), Tác động phi tuyến tính của rủi ro tín dụng đến tỷ suất sinh lời tại các ngân hàng thương mại cổ phần Việt Nam, Tạp chí Kinh tế & Phát triển, Số 281 (II), trang 117-126 4. Phan Thị Thu Hà & Trần Thị Thanh Diệu (2021), Tác động của hoạt động ngoại bảng đến tỷ suất sinh lời tại các ngân hàng thương mại cổ phần Việt Nam, Tạp chí Kinh tế & Phát triển, Số 283, trang 34-44 5. Dieu Thi Thanh Tran & Ha Thi Thu Phan (2019), The impact of Off-balance sheet credit risk exposure on bank performance in Vietnam, International conference on Business and Finance (ICBF), University of Economics Ho Chi Minh City (UEH), 23 August 2019

limited, factors on the macro environment such as exchange rates and

interest rates have not been mentioned.

The above limitations will be the premise for the author to carry

out further studies in the near future.