The U.S. Securities and Exchange Commission wants issuers of target-date investment funds to use tag lines to describe fund asset allocations.

A fund tag line, which would come immediately after a fund’s name, should say what percentage of the assets are in stocks, what percentage in bonds, and what percentage in cash, officials say.

Members of the SEC today voted 5-0 to ask for public comments on the proposal.

Target-date funds include mutual funds, and investment options on variable annuity and variable life investment menus, that are designed to become more conservative as workers near retirement age.

The funds for older workers turned out to be less conservative and more volatile than many participants had expected in 2008 and 2009, SEC Chairman Mary Schapiro said today before commissioners voted on the proposal.

“Imminent retirees invested in 2010 target date funds saw, on average, 24% of their funds’ assets evaporate in 2008,” Schapiro said.

Simply requiring investment managers to add warnings to prospectuses and related documents is not enough, because “investors in target-date funds are, almost by definition, not active market observers or researchers,” Schapiro said. “The best place to reach them is through marketing and advertising materials.”

The tag line could help give important information to investors who would be overwhelmed by more complicated financial information, Schapiro said.

The proposal would let companies put ranges such as “40-45% in equity” in the tag lines.

“I am particularly interested in public comment on whether such ranges are appropriate, or whether they should be constricted in order to foster investor understanding,” Schapiro said.

The proposals also would require target-date fund marketing materials to include a visual depiction — such as a table, chart, or graph — showing a fund’s glide path over time, and they would require target-date fund marketing materials to include a statement of the fund’s asset allocation at the “landing point,” or participants’ anticipated retirement date.