When someone puts a figure in box B5 (banked target) I want it to change the percentage to whatever it should be according to the right. So less than £100k = 0%, £100k-£114,999.99 = 3% and so on
Use vlookup. Put the %'s in column G (at the other side of the £ figures). The % can then be looked up by putting =vlookup(B5,F1:G5,2,TRUE) in cell B1. The TRUE param tells vlookup to make an inexact match, it will match to the closest figure below whatever you put in B5. So £114,000 will match to 3%, anything above £150K will match to G5 and anything below £100K will return N/A.