Billionaire Stan Druckenmiller is glad he’s no longer in the hedge fund business now that algorithmic and quantitative trading have taken over markets. “I made 30 percent a year for 30 years. Now, we aren’t even in the same zip code, much less the same state,” he quipped of his recent returns in an interview with Bloomberg Television. Druckenmiller, 65, explained that his investment process has always involved divining so-called market signals. But quantitative funds, which now account for $1 trillion in assets, have muted or even silenced those cues, making it a lot less clear what’s behind price moves.