Looking further out, Cerulli said 71 percent of advisors will leave the business within two decades.

Most of the growth will be in defined contribution plans, although a report from PricewaterhouseCoopers says traditional pension plans will remain viable until mid-century.

Participants in a study who were given the chance to consider several policy changes to shore up the Social Security system favored reducing payments to high wage earners, raising the retirement age and other remedies that would eliminate most of the systems debt.

The Milliman 100 Pension Funding Index found that the funding ratio of the plans fell from 95.2 percent to 91.2 percent, which translated to a $67 billion rise in unfunded liabilities to a total of $140 billion.

At issue in Fifth Third Bancorp v. Dudenhoeffer is whether the presumption that employers act prudently when offering their own stock will remain a guiding principle.

At the end of the third quarter, recordkeepers reported that 18.3 percent of participants had outstanding loans. Before the Great Recession began in 2008, the rate had been 15.3 percent.

In a letter to the board, Gov. Brown said increased longevity would cost the system $1.2 billion more per year than today.

After the U.S., where assets rose 12 percent to $18.9 trillion, were Japan with 10.2 percent of assets, and the United Kingdom, with 10.1 percent.