I want to make a table that will calculate interest on overdue bills. the
problem i've hit is that we have a variable interest rate that is charged.
its dependant on the bank of england base rate. so between certain dates it
will be charged at one value and between other dates it will provide another.
im doing this back to 2000 so there are alot of changes in the interest rate.
for example between 01/07/09 and 01/08/09 the base rate stood at 4% so 4%
interest can be charged.
we can charge interest from 05/07/09 (when the bill was sent)
so i do a conditional formula that if 05/07/09 is less than 01/08/09 but
greater than 01/07/09 then the value 4% will be charged
i need the cell that i put this formula in to test against 30 different date
ranges each with a different rate of interest applicable
so when i put a date in a cell the conditional format checks to see if it
lies within these date ranges and then the cell appears as the applicable
rate of interest.

sorry if this isn't clear it may not even be conditional formatting that i
need to look at, any help much appreciated though