http://www.bloomberg.com/apps/news?pid=20601087&sid=acmiX_sr8yuc&refer=home âWeâre going to continue to see very volatile markets,â said Ron Rimkus, a money manager for Raleigh-based BB&T Asset Management, which oversees $17 billion. âThereâs nothing good going on in terms of the economy.â Father of Value Investing Benjamin Graham, the father of value investing and mentor of Buffett, would find most U.S. stocks expensive even after the S&P 500 dropped 56 percent in 17 months. Graham measured equities against a decade of profits to smooth out distortions, a method that shows the S&P 500 trading at 13.2 times earnings, according to data compiled by Yale University Professor Robert Shiller. At the bottom of the three worst recessions since 1929, the average ratio fell below 10. To reach that level, the S&P 500 would sink another 27 percent." Investors who valued companies based on earnings or forecasts covering just one year have been burned as equities kept dropping. The S&P 500 fetched 16.2 times its companiesâ 12- month profits on Jan. 7, the lowest since at least 1998, according to data compiled by Bloomberg. The index has since declined as much as 25 percent to a 12-year low.