Progressive percentage reduction

[Gref]

I would like to calculate a .5% reduction of a number over a 10 year period with the .5% reduction calculated on the previous reduction. Example 100 - .5% = 99.5, then 99.5 - .5% = 99.0025, then 99.0025 - 5% = 98.52988. I tried a simple =c45-.5% but that doesn't work. I know it's probably something simple, but I'm just learning.

 

[MARK858]

Excel 2010
	C
45	100
46	99.5
47	99.0025
48	98.50749
49	98.01495
General Manager Report

Cell Formulas
Range	Formula
C46	=C45-(C45*0.5%)
C47	=C46-(C46*0.5%)
C48	=C47-(C47*0.5%)
C49	=C48-(C48*0.5%)

I don't know where you get the below from

99.0025 - 5% = 98.52988

 

[MickG]

Try:-

=100/1.005^10