Nguyen Phu Ha

The COVID-19 pandemic highlighted the sensitivity of connectedness among bank stock returns in Vietnam. The aim of this study is to examine the strength of this connectedness along with the effect of government lockdown policy and COVID-19 cases on the total connectedness index (TCI) of 16 listed banks on Vietnamese stock exchanges. They are assessed using the database of FiinPro on the banking sector between January 2020 and July 2022, Vietnam Center for Disease Control and Prevention (CDC), and The World Health Organization (WHO) on the COVID-19 pandemic, employing a time-varying-parameter vector autoregressive (TVP-VAR) connectedness framework and the conditional quantile regression model.
The results show that at the firm level, there is strong interdependence among bank stock returns with the average TCI being as high as 90.66%. It is also revealed that medium and large-sized banks are receivers of shock, while smaller banks are transmitters. As far as the impact on TCI is concerned, the widespread of the pandemic with the increasing number of COVID-19 cases is significantly negative, whereas the tightening of lockdown is significantly positive. Besides, the degree of the impact varies according to the 95th, 75th, 50th and 25th levels of conditional quantile regression. Based on the study’s findings, individual investors are recommended to thoroughly analyze the connectedness of banks before making investment decisions, while bank regulators should strengthen controls on credit relationships with small banks. Regarding policy makers, it is proposed to apply flexible restrictions and short-term lockdown depending on the actual outbreak of the pandemic.

Acknowledgment
The paper was conducted within the scope of Project QG21.48 of Vietnam National University.

Shares of listed banks in Vietnam gain a lot of interest from investors and regulators. It is important to study the primary drivers of the banks’ share prices. In this context, Gross Domestic Product (GDP), Gold Price (GP), Ninety-day Interbank Interest Rate (R), and USD/VND Exchange Rate (FX) are selected as representatives for macroeconomic variables. A new contribution of this study is the application of interactive factors between macroeconomics and bank performance (i.e., Equity Capital (E), Deposit Аmounts (D), Loan Amounts (L), Non-performing Loans (NPLs), Leverage (LEV), Capital Adequacy Ratio (CAR), Return on Assets (ROA), and Stock Beta (Beta)) in evaluating their impact on bank share prices. Applying the econometric method of Two-Stage Least Square (2SLS) and the quarterly financial data of 13 listed banks from Q1/2009 to Q3/2020, the regression results show that GDP improvements can foster an increase in bank share prices, and this impact is strengthened if banks have good performance of ROA, CAR, and with strict control of NPLs. The R also has a positive impact on bank share prices, and the price level increases if NPLs, LEV, and Beta are controlled at optimal levels. However, empirical evidence drawn from the study also suggests that an increase in FX and GP is not a significant contributor to bank share prices, especially if the bank does not manage NPLs and LEV. Moreover, the impact of E, D, and L on the movements of bank share prices is not significant.