The Thrift Savings Plan's fund returns are showing sustained signs of life after the dismal 2008 stock market.

Aside from a 1 percent drop in the I Fund's international stocks in June, all five underlying funds have shown positive returns since March, according to the board governing TSP.

And the streak is likely to continue this month, said Tracey Ray, chief investment officer of the Federal Retirement Thrift Investment Board. The C Fund, which tracks larger U.S. companies, is up 2.4 percent so far in July, she said. The S Fund, which is pegged to small- and medium-sized U.S. companies, is up 1.9 percent, and the I Fund is up 1.4 percent.

"The sizzle is back in July," Ray said today at the board's monthly meeting in Washington. "We're on track for five months in a row of [mostly] positive performance."

Board chairman Andrew Saul said investors remain largely conservative since the 2008 crash — which wiped out between 37 percent and 42 percent of the three stock-based funds' value — and continue to invest heavily in the government securities-backed G Fund. The G Fund does not decline in value and yields only modest returns.

But TSP participants are apparently regaining confidence in the market. For the third straight month, participants in June moved nearly $1 billion from the G Fund and the F Fund's bonds into the stock-based funds.

And the TSP's L Funds, or lifecycle funds, attracted high numbers of participants in June. Nearly 602,000 participants had L Fund balances in June. That is the most since August 2008, when more than 600,000 had L Fund balances.

Under the L Funds, TSP invests in a mix of the five underlying funds and adjusts them to become more conservative over time.

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