Kolkata: ESAF Small Finance Bank earned a Rs 160 crore net profit in the second quarter of the fiscal year, as compared with Rs 80 crore in the first quarter and a Rs 116 crore loss in the year-ago period. The bank returned to profitability in the third quarter of the last fiscal year after incurring losses for the previous five quarters due to high credit costs stemming from asset quality stress in the microfinance sector.Its net interest margin for the quarter improved to 8.2% from 5.9% seen for the year-ago period.ESAF's pre-provision operating profit for the quarter under review rose nearly four times to Rs 362 crore from Rs 93 crore in the corresponding period last year.