Infrastructure investment trust IndiGrid on Thursday reported a 31 per cent drop in consolidated net profit at Rs 68.69 crore for the March quarter, impacted by expenditure on acquisitions. The consolidated net profit of the India Grid Trust (IndiGrid) was Rs 99.67 crore in the corresponding period of the previous year, it said in a BSE filing. The PAT (profit after tax) is lower because of one-time expenditure for BDTCL (Bhopal Dhule Transmission Company Ltd). Interest cost is higher because of recent acquisitions of over Rs 5,000 crore in Q4 (January-March), a company official said. Total income rose to Rs 514.09 crore in the quarter from Rs 335.32 crore in the same period a year ago.