The average yield inched down on 273-day treasury bills auctioned by Egypt's central bank on Sunday, the bank said. The average yield edged down to 15.5 percent from 15.6 percent at the last issue on April 10 and the bank sold all of the 3.5 billion Egyptian pounds of bills it had sought. The average yield on 91-day bills inched up to 13.938 percent from 13.905 at last week's auction. The central bank sells the bills on behalf of the finance ministry. http://english.ahram.org.eg/News/39914.aspx