HDFC Bank saw a rise of 20 percent in profit in the first quarter, backed by a rise in revenue and a reduction in cost-to-income ratio. The private sector lender's net profit rose 20 percent to Rs 3,893 crore in the quarter ended June from Rs 3,239 crore in the year-ago quarter. Analysts say that HDFC Bank's performance exceeded expectations on most operating performances. This was despite the marginal impact on asset quality due to the spate of farm-loan waiver demands across the country. Net interest income, the difference between interest earned and interest expended, was Rs 9,370 crore in the June quarter, 20 percent more than Rs 7,781 crore in the year-ago period. Other income, mainly fees and commission, grew 25 percent to Rs 3,517 crore in June from Rs 2,806 crore previously. Net interest margin, a key indicator of the bank's stability, was 4.4 percent for the June quarter.