Treasury bill is short-term debt obligation backed by the U.S. government with a maturity of less than one year. T-bills are sold in denominations of $1,000 up to a maximum purchase of $5 million and commonly have maturities of one month (four weeks), three months (13 weeks) or six months (26 weeks). T-bills are issued through a competitive bidding process at a discount from par, which means that rather than paying fixed interest payments like conventional bonds, the appreciation of the bond provides the return to the holder. (http://www.investopedia.com/terms/t/treasurybill.asp) Iranian capital market after Islamic revolution experienced issuance of treasury bills for a maturity of 5.5 months in September 2015. The issuance value was 10 billion Iranian Rial and traded in the market on the basis of discounting in Iranian Islamic capital market.