Check out this T-Bill maturing on 23-06-2023. Today’s date is 03-05-2023
Days left for maturity = 51
T-Bills are issued at discount and are redeemed at par. So this bond if bought at 98.80 will give 100 after 51 days. That is about a profit of Rs. 1.2.
ROI = ( [Profit] / [Face Value] ) * [ 365 / Days to Maturity ]
Hence, the ROI (annualized) would be (1.2/98.80) X (365/51) x 100 = 8.69%
Disclaimer: This is not a trade / investment recommendation, just analytics of market dis-equilibrium.