# Difference between Excel's Rate Function and Paul Wilmott's Goal Seek Method for finding YTM

I'm watching some FRM videos teaching how to find YTM via excel's =rate() function and tried getting the YTM using Paul Wilmott's spreadsheet that uses goal seek. I'm getting different results.

First the rate() formula:

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Now the goal seek method:

• How did you get 3.347% using Rate () function in excel? I got 3% in excel using the same data. – Dhamnekar Winod Jul 14 '18 at 4:49
• Maybe your value is rounded off – gaston Jul 16 '18 at 14:06

Notice that $e^{0.0658}=1.03347\times2$. That is how your answer 3.347 per period and his answer 6.58 for 1 year can be reconciled. He is working with $e^{rt}$ and you are working with $(1+r)^n$. Your answer is the industry standard method for finding YTM for US Treasuries, his answer is for quants who like to express all interest rates in continuous time.