Please confirm the duration numbers (show the calculations) for maturities at 4, 10, 15, and 20 on slide #19, L2 T

Use the following info and show all excel calculations.

Example: Determining Duration Number of years to maturity Price at 9% Price at 9.5%(P+) Price at 8.5% (P) Duration 4 870.41 855.80 885.35 10 743.29 717.45 770.35 7.12 P- Pt 2(P) (0.005) 15 677.57 647.73 709.35 20 634.86 603.44 668.78 10.29 0 3.40 9.09 Duration = 19 Pricing of Financial Assets