Where can I see a historical graph of % net profit margin for the S&P 500?

Question

Where can I see a historical graph of % net profit margin for the S&P 500?

Answer 1

i doubt anyone has ever taken the time to make it.  it really would be pretty meaningless - you'd have financials pulling it up with their 90% margins, and energy companies weighting it down with their 5% margins.

the S&P 500 is simply too large for a stat like that to say anything meaningful.