An investor wants to find the duration of a(n) 20-year, 5% semiannual pay, noncallable bond that's currently priced in the market at $631.97, to yield 9%. Using a 100 basis point change in yield, find the effective duration of this bond

The new price of the bond if the market interest rate decreases by 100 basis points (or 1%) is $________ (round to the nearest cent)