Looks like you may have solved it however there are actually a number of ways you could do this.
The original formula has the following problems.
- You don't need it enclosed in a SUM formula when you have the plus sign between the 2 components however it will still work.
- The AND component is being used incorrectly.
- In a nested IF as you have done you need to reverse the order otherwise it meets the first test, returns 5 and evaluated no further for the higher strike rates.
- Theoretically you should also change it to N2>=120 rather than N2>119.99 because there are values between 119.99 and 120 where you don't want the bonus applied however given the numbers that will be relevant here that shouldn't be a problem.
Using a nested if I would recommend the following.
=I2+IF(I2<20,0,IF(N2>=160,25,IF(N2>=150,20,IF(N2>=140,15,IF(N2>=130,10,IF(N2>=120,5,0))))))
However the tidiest way is probably with a VLOOKUP as follows.
View attachment 22825