Reduce / efficiency formula

Hello,

Because I have many formulas in a spreadsheet trying to reduce their number.
How can I reduce / efficiency this formula:

=IF(AND(B4>=1900;B4<2000);AB20;IF(AND($B$4>=2000;$B$4<2100);AC20;IF(AND(B4>=2100;B4<2200);AC20+1;IF(AND(B4>=2200;B4<2300);AC20+2;IF(AND(B4>=2300;B4<10000);AC20+3)))))

Re: Reduce / efficiency formula

Thanks for reply,

I dont want to change "if" with vlookup. I want to make more flexible formula if is possibil.

Re: Reduce / efficiency formula

Thank you AAE.

Re: Reduce / efficiency formula

Thank You snb.