I'm using a function to put a price in a cell depending on how many days have passed. So 1 day = $10, 2 days = $20, 3 days = $30 and I do it like this...

A1 (start date) = 01/01/2011
B1 (end date) = 01/01/2011
C1 (days) = 1
D1 (price) = $10

But after 30 days I want to put in a discounted price (so 31 days would be $305 not $310) and this is where I get stuck. My code goes something like this (I'm not in front of the same computer right now)...

Code:
elseif days > 30 then
x = range("c31") - 30
price = 300 + (x * 5)
Initially the code worked but then after copying and pasting the code into other cells/rows below it, I was getting the wrong result. I think it's because I'm referencing the cell directly "C31". I think I need to program it so that when I copy and paste the cells contents the reference to the cell changes too (eg - C31 to C32) but I can't work out how to fix this problem. So can anyone point me in the right direction? Thanks.