To determine the percent change in price, solve for the differences between the original prices and the sale prices. Then, divide the difference by the original price and multiply by 100%.
The formula of the future value of annuity ordinary Fv=pmt [(1+r)^(n)-1)÷r] Fv future value Pmt payment per year 4000 R interest rate 0.0215 N time 5 years