Since the COVID-19 pandemic spread among the world, the banking sector has experienced a decline in its level of efficiency (Zheng and Zhang, 2021) as well as a decrease in the quality of the loan portfolio (Ratnovski et al., 2020) which simultaneously affects access to capital which has become limited, especially from the market. capital due to a downgrade of credit ratings and an increased risk of bankruptcy in the corporate sector, except for high-quality issuers (Mirza et al., 2020) which can lead to vulnerabilities in developing country credit markets or can even cause a new financial crisis.
The impact of COVID-19 has slowed the progress of the global economy, resulting in financial institutions facing several problems. These linkages can lead to vulnerabilities in institutional networks which will ultimately impact the financial system as a whole. In the previous period, Islamic banks have demonstrated resilience during the global financial crisis due to the different nature of risk sharing applied to their business models from conventional banks. One of the fundamental differences between the global financial crisis and the COVID-19 pandemic crisis is the current COVID-19 crisis is an exogenous shock means the entire economy has halted due to the lockdown policy and the implementation of social restrictions. Due to the existence of different types of policies, it is hoped that Islamic banks will be able to face challenges for their sustainability just like conventional banks.
This research is empirically to compare the level of efficiency between conventional banks and Islamic banks in Indonesia in two periods, before and during the COVID-19 pandemic by investigating some factors; the effect of assets, equity, deposits, number of employees, number of offices, as well as other variables. Besides comparing the level of efficiency, this study analyzes data from the two types of banks from two periods before and during the COVID-19 by using DEA. There are two reasons why this research was conduted in Indonesia, namely first, Indonesia is a country with the largest Muslim population in the world, so that it can be said that the growth between Islamic banks and conventional banks is developing equally rapidly. Second, Indonesia is a country exposed to quite a severe impact from the COVID-19 pandemic.
This research also shows several important findings regarding the two banks. First, the function of two types of banking are different and these differences persist even after controlling for bank-specific variables. Second, conventional banks are more stable in terms of technical both in the period before and during the pandemic compared to Islamic banks. However, the average value of the research in time span, Islamic banks are considered more efficient, both before the pandemic and after. Third, the efficiency productivity of conventional banks appear to be more efficient than Islamic banks when assessed from the movement of efficiency scores per period. However, the overall average score in the period before and after the pandemic, Islamicl banks are having improvement. Fourth, the efficiency level of Islamic banks before COVID-19 was better compared to conventional banks by looking at the total factor productivity change. It can be seen in the period during COVID-19 showed that Islamic banks were more efficient than conventional banks.
Based on the findings above, it can be said that conventional bank indicators have a more dominant impact on the COVID-19 pandemic, while the impact on Islamic banks is relatively smaller. This substance causes the performance of Islamic banks to be relatively better than conventional banks in facing the global financial crisis. Therefore, the findings from this study support the current claim that Islamic banking is superior to conventional banking according to the findings of Imam and Kpaordar (2010), Alaro and Hakeem (2011), Rahim and Zakaria (2013), Rashid et al. al. (2017), Odeduntan et al. (2016), Miah and Udin (2017), which contrast the findings of Kassim and Majid (2010), Hasan and Dridin (2011), Abdulle and Kasim (2012), Alqahtani and Mayes (2018).
During the research period and different economic conditions, there is no significant difference between conventional banks and Islamic banks in terms of efficiency. Islamic banks are considered more efficient when compared to conventional banks in terms of total factor productivity change both in the period before and during the pandemic. These findings support the argument that Islamic banks should not be overly affected by the global financial crisis because in Islamic banking principles, most of the financial transactions and contracts that are believed to be responsible for the crisis are unacceptable (ahmed, 2009).
This study aims to compare the efficiency levels of conventional banks and Islamic banks in the period before and during COVID-19. The analysis conducted shows that Islamic banks are more efficient than conventional banks, both in the period before and during COVID-19 pandemic

This study compare of efficiency between conventional and Islamic banks in two periods, namely before and during COVID-19 by looking at the effect of assets, equity, deposits, employees, and number of offices on banking financial performance for the 2010-2021. The data came from 29 banks in Indonesia which were analyzed using Data Envelopment Analysis. The results show that conventional banks are more stable in terms of technical during the two periods. However, when viewed from the average technical change value over the research timeframe, Islamic banks are considered more efficient. Furthermore, based on the efficiency of total factor productivity, conventional banks look more efficient based on the movement of efficiency values per year, in contrast to the overall average score which shows Islamic banks are considered better. The results show that the efficiency level of Islamic banks before and during COVID-19 are more efficient based on changes in total factor productivity, which indicates that the COVID-19 has had a more dominant impact on conventional bank compared to Islamic banks.

Abstract iv
Chapter 1 Introduction 1
1.1 Research background 1
1.2 Differences of Islamic and conventional banking 1
1.3 Research Question 4
Chapter II Literature Review 7
2.1 Islamic and Conventional Banking 7
Chapter III Data and methodology 13
3.1 Data 13
3.2 Methodology 15
3.3 DEA (Data Envelopment Analysis) 18
3.4 Malmquist Productivity Index 27
Chapter IV Emperical Result 31
4.1 Descriptive Statistics 31
4.2 Malmquist Total Factor Productivity Index 46
Chapter V Conclusion 49
5.1 Discussion and Conclusion 49
5.2 Limitation of the Research 52
5.3 Future Research 52
References 53

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