Dollar on Wednesday surged by Rs2.60 and reached Rs161.60 in the inter-bank market at the end of the day, the state bank said.
Meanwhile, in the open market, the dollar exchange rate was Rs160 after rising by Rs1.50.
On March 24, a Rs94.6-million foreign investment was made in the government's T-Bills.
Foreign investors have sold nearly Rs1.50 billion worth of T-bills in March, whereas foreign investment in the T-bills from July 1 to March 24 stands at Rs1.60 billion.