Right now... P/E means SQUAT!!! There is so much irrationality going on right now.... and so little profits being made... that P/E is just not a good indicator.
Pay close attention to Price/Sales, Revenue/Employee, Cash-on-hand, and.... well, I'm sure there are a lot more... but these are some important ones. Price to forward looking earnings is also a better one than just P/E.
Right now, for a DIGITAL company, such as AMD.... Price/Sales is between 1x and 4x. So.... take MarketCap/YearlyRevenue.... == 1x - 4x. I don't know what it is right now for AMD... but I'm thinking its probably around 2x - 3x.
For a mixed-signal IC company, such as TI or Analog Devices... I bet the number is closer to 5x or 10x.
Rev/Employee is pretty good at $250k/employee.... smoking if closer to $500k/employee. Check out the cash position too.... if the company is valued at $2/share... but the company has $3/share cash in the bank... well, you know that either there are some phony numbers in the accounting thing, or that the company has been unjustly beat down (this is an extreme case, but you get the picture).
Hope this helps.
DISCLAIMER: I am not a stock broker/trader, am not involved in professional trading, etc. Please do your own research. The above suggestions/comments may or may not help/improve your trading strategy.
