JOHANNESBURG (Reuters) - South Africa sold 3.36 billion rand worth of three-month Treasury Bills on Friday - less than the 3.685 billion rand on offer - at an average yield of 5.31 percent from 5.25 percent last week. The bid-to-cover ratio was at 0.9. Auction date: 27/12/2013 Settlement date: 02/01/2014 Days 90 181 272 363 Amount received (R'bln) 3.46 3.74 3.325 4.83 Amount allotted (R'bln) 3.36 1.665 1.3 1.12 Amount on offer (R'bln) 3.685 1.665 1.3 1.12 Bid-to-cover ratio 0.9 2.2 2.6 4.3 Avg discount rate (pct) 5.24 5.6 5.71 5.75 Average yield (pct) 5.31 5.76 5.96 6.1 For details of the auction double-click on