Calculating rebate

[st_judeu@yahoo.com]

Good day friends.

Please I have a file for calculating customers' rebate as follows:

<=500 No rebate
501-1000 4%
1001-1500 4.5%
1501-2000 5%
2001-2500 5.5%
2501-3000 6%
3001-3500 6.5%
3501-4000 7%
4001-4500 7.5%
4501-5000 8%
5001-5500 8.5%
5501-6000 9%
6001-6500 9.5%
6501-7000 10%.
My challenge here is that I tried using IF function and the system is saying this is too long for nested formular. What formular can I use to incorporate all the conditions? Thank you.