Mahanagar Telephone Nigam (MTNL) today reported a 38% decline in net profit at Rs 578.68 crore for the year ended March 31, 2006 when compared with Rs 938.98 crore in FY05.According to a release issued by the company to the BSE today, total income declined to Rs 5,785.58 crore in FY06 from Rs 6,084.11 crore in FY05.