Note(s): Results of the determinants of excess of NPLs. In columns (1), the dependent variable is the excess of NPLs resulting from their breakdown obtained by means of the stochastic frontier, column (2) the dependent variable is represented by the minimum level of NPLs on the stochastic frontier and column (3), which provides a comparison with the determinants of the overall NPLs. Results of the determinants of Excess of NPLs. In columns (1) and (2), the dependent variable is the excess of NPLs resulting from their breakdown obtained by means of the stochastic frontier, column (3) the dependent variable is represented by the minimum level of NPLs on the stochastic frontier and column (4), which provides a comparison with the determinants of the overall NPLs. The independent variables are:TIER1_i,t−1 capital ratio; ROA_i,t−1 is the return on asset ratio between profit before taxes and total assets; GLGR_i,t−1, i.e. the gross loan growth rate; Cost-to-Income_i,t−1 is the cost-to-income ratio measured by operating expenses over the intermediation margin; GDP growth_t−1 captures the macroeconomic conditions or business cycle for Italy; Size_i,t−1 is the natural logarithm of total assets. Mutual North East, Mutual Centre and Mutual South are dummy variables which capture the marginal effects for mutual banks; Sample period: 2006–2017; *, **, ***denote the 10%, 5% and 1% significance level, respectively