Younger investors were more likely to take their assets and head for the exits last year than their older counterparts, a study by Aite Group reports.  It’s not unusual for Gen X and Gen Y investors to move money, since they’re likely to face life choices (such as buying houses or having a child) more often than their parents and grandparents. But the sizable share of younger investors (28 percent) that are willing to pull their money from large brokerages or the investment units of retail banks should give pause to those firms, since the investors’ current and future wealth makes them attractive clients. —JG