Short of reviving the heyday of defined benefit pension plans, automatic enrollment in defined contribution plans has been considered the best hope for addressing America's retirement crisis. By default, sponsors automatically deduct a specified amount from employees' paychecks and allow them to opt out they wish. But how high should that deduction be? At what threshold do employees exercise their option to quit the plan?

Probably higher than the 3 percent default level set by the Pension Protection Act of 2006, according to a recent bulletin from the Employee Benefit Research Institute.

Though 42 percent of people surveyed say they would continue contributing at that level, 44 percent say they'd be happy to contribute at twice that rate. Eleven percent don't feel that a 6 percent deferral is high enough and would increase it.