如何正确循环这个乘法？

Question

我试图计算一个物体在20年内的折旧，每年按其原值的15%计算。问题是它只将第一次乘法的结果减去循环的其余部分，而不是将值减少15%20倍

ovalue = int(input("Enter the value of the car: "))
res = ovalue * 0.15
fvalue = ovalue - res
year = 1
while (year <= 20):
   print("Year ",year,":", fvalue)
   year = year+1
   fvalue = fvalue-res

有办法解决这个问题吗？多谢各位

Answer 1

price = []
for i in range(1,20):
    value -= value*0.15
    price.append(value)

Answer 2

这将在每次迭代中将该值减少当前值的15%

value = int(input("Enter the value of the car: "))

year = 1
while year <= 20:
   value -= value * 0.15
   print("Year ",year,":", value)
   year = year+1

这将在每次迭代时将值减少原始值的15%（这可能不是您想要的）

value = int(input("Enter the value of the car: "))

deduction = value * 0.15
year = 1
while year <= 20:
   value -= deduction
   print("Year ",year,":", value)
   year = year+1

Answer 3

正如许多人所说，你想乘以折旧值。注意，如果它贬值15%，它的新值将是当前值的85%。因为这是乘法，所以我们可以使用幂

def depreciate(initialValue, depreciationRate, numYears):
    depreciationRate = 1 - depreciationRate
    return initialValue * (depreciationRate ** numYears)