God this should be such an easy thing, but for the 2008 PE multiple of a company, do you use the average price for 2008? Or the price at 12/31/08? If you say “average”, what about EV/EBITDA? For the EV part, would you take an average of the net debt and add it to the average market cap (based on avg 2008 price * shares)?
I would use static dates not averages.
Price is usually static… the Earnings number can be normalized in different ways.