How are you calculating value created? Based on market capitalization it looks like the S&P 500 went from a market cap of $925 Billion in the 1980's to over $19

How are you calculating value created? Based on market capitalization it looks like the S&P 500 went from a market cap of $925 Billion in the 1980's to over $19 Trillion today [1]. [1] http://siblisresearch.com/data/total-market-cap-sp-500/ http://siblisresearch.com/data/total-market-cap-sp-500/