Any Excel gurus out there?
I'm making a spreadsheet comparing overall costs of CFL light bulbs with those of tungsten bulbs. Working out the running costs is easy, what I'm struggling with is factoring in the capital costs of the bulbs. The tungsten bulbs last for, say, 1000 hours and cost 50p each and the CFLs last 8000 hours and cost £5 each. What I want to do is add these costs as a discrete value every 1000 and 8000 hours. Is there a simple way to do this??