The very truth of stocks with broad market

"50% of a stock’s price movement can be attributed to the overall movement in the market, 30% to the movement in its sector and only 20% on its own."

---The Latent Statistical Structure of Securities Price Changes

“Of a stock’s move, 31% can be attributed to the general stock market, 12% to the industry influence, and 37% to the influence of other groupings, and the remaining 20% is peculiar to the one stock.”

---(Market and Industry Factors in Stock Price Behaviour, Journal of Business, January 1966)

The very truth of the individual stock with the broad market that Benjamin F. King, a Professor in University of Chicago, wrote to Journal of Business in 1964~1966.

Thanks to Joe the stock chartist.