Threshold Equation Help
 

I'm trying to set up a calculator for the following information.

Range Percent Per Point
1-100 = 0.10
101-500 = 0.025
501-1000 = 0.02
1001-8000 = 0.01

The calculator should allow the user to enter a number within the range and then calculate a total percentage based on the percent per points.

ex. user enters 600
100 points * .10 = 10%
399 points * 0.25 = 9.975%
101 points * 0.02 = 2.02%
for a combined total of 21.995%

The calculator would then display 21.995% in a cell next to where the user entered 600. Please post the equation. Thank you in advance.

-Kevin.