PORT LOUIS (Reuters) - The weighted average yield on Mauritius' 273-day Treasury bill fell to 2.64 percent from 3.24 percent at the previous sale on Dec. 30, the central bank said. The bank sold all the 500 million rupees ($15.3 million) worth of bills on offer at the auction which was held on Friday, but results published on Tuesday. It received bids worth 1.965 billion rupees at yields ranging from 2.45 percent to 4.20 percent. ($1 = 32.7600 Mauritius rupees)