How do you calculate the compounded growth rate where:
base year is 2,969 and current year is 20,912 after 25 years.
Use the formula: A = Pert
where A = final amount = 20 912 P = initial amount = 2 969
r = rate (as a decimal) t = time = 25
Substituting: 20 912 = 2 969e25r
Dividing both sides by 2 969: 7.043434 = e25r
Take the ln of both sides: ln(7.0434) = ln(e25r)
ln(7.0434) =25r
Divide by 25: r = ln(7.0434) / 25 ---> r = 0.078 ---> r = 7.8% (approx)