1. Suppose today is September 26, and you are considering buying one call option expiring on October 26.

You need to estimate the risk-free interest rate for that option. You obtain the following US Treasury bill quota from Wall Street Journal.

Treasury bill bid and ask data are representative over-the-counter quotations as of 3pm Eastern time quoted as a discount to face value. Treasury bill yields are to maturity and based on the asked quote.

Maturity	Bid	Asked	Chg	asked yield
9/13/2018	1.868	1.858	0.010	1.884
9/20/2018	1.878	1.868	-0.013	1.894
9/27/2018	1.875	1.865	-0.010	1.893
10/4/2018	1.938	1.928	-0.008	1.957
10/11/2018	1.968	1.958	-0.005	1.988
10/18/2018	1.995	1.985	-0.007	2.017
10/25/2018	2.015	2.005	-0.010	2.038

Use the information above to find out the risk-free interest rate.