During more than a week of stock market sell-offs, investors have been exhorted to use declines to pick up bargains – and with a 7.7 percent drop on the S&P 500 since August 17, stocks have certainly gotten less expensive. By several of those metrics, the bottom line is this: U.S. stocks are not wildly expensive, but they are not the screaming bargains that might pull value-minded investors back into the market. “We are not getting to a point where it’s attractive, it’s just not as expensive,” said Michael O’Rourke, chief market strategist at JonesTrading in Greenwich, Connecticut.