Steel Authority of India (SAIL) today reported a 31.5% rise in net profit (standalone) at Rs 1,934.66 crore for the third quarter ended December 31, 2007, when compared with Rs 1,471.19 crore in the corresponding quarter a year ago.According to a release issued by SAIL to the BSE today, total income increased 12.4% to Rs 9,847.64 crore for Q3FY08 from Rs 8,760.16 crore in the quarter ended December, 2006.