بهره وری شعبه بانک تحت تغییرات محیط زیست: DEA راه انداز بر اساس گزارشات حسابداری سود و زیان ماهانه شعبات خرده فروشی یونان Bank branch efficiency under environmental change: a bootstrap DEA on monthly Profit and Loss accounting statements of Greek retail branches

1. Introduction Nowadays a turbulent economic environment stimulates researchers to measure efficiency and performance change in diverse types of businesses. Banks, in particular, are mostly affected by recessions and economic downturns that might cause inefficiency. Fethi and Pasiouras (2010, p. 196) suggest that the estimation of bank branch efficiency over successive time periods is an important area of research deserving special attention. The specific suggestion motivates us to provide an efficiency measurement at bank branch level, taking systematically into account substantial external environmental alteration and diverse stages of recession.1 More specifically we contrast expansion and recession effects, emphasizing capital control effects that constitute a unique phenomenon in the postwar period in the Eurozone. To the best of our knowledge, this is the first study that provides an in-depth empirical analysis of efficiency change at bottom-level banking across successive stages of recession. But above all the factor that makes our paper original is its focus on the very turbulent period of capital controls since their significance (as that of the Greek crisis as a whole) stretches beyond the borders of Greece, and attracts the interest of academics, bank managers, regulators, and policy makers seeking to explain the nature and the implications of the specific totally unexplored and unpredicted phenomenon that lasts until today (December 2016). Capital controls initially causing the inactivation of important banking function operations given the bank holiday that took place (end-month June 2015), then helped stabilize the liquidity of the banking system through the restraint of deposit outflows and capital transfers abroad. Thus, we offer an attractive case study representing the crisis bank-driven Greek economy that is a member of the Eurozone and its banking institutions are an integral part of the single European monetary system supervised by the ECB and also characterized by similar banking operations (pure retail banking) with other EU peripheral countries.