Punjab National Bank has recorded 6.6% increase in net profit at Rs 538 crore in the July-September quarter of 2007-08 (Q2FY08) when compared with Rs 505 crore in Q2FY07.The net profit of the bank rose 10.4% during the fist half of this fiscal (April- September period) at Rs 963 crore compared to Rs 872 crore in the corresponding period last fiscal.