December marks another winning month for TSP

International stocks are biggest performers, gaining 4.64 percent.

December was another sound month for Thrift Savings Plan investments, with all of the funds seeing increases.

The international stocks (I) fund performed especially well, growing 4.64 percent during the month to bring its total 2005 increase to 13.63 percent.

The F Fund, made up of fixed-income bonds, was the second-highest earner in the government's 401(k)-style retirement savings program, showing a 0.95 percent increase in December. The ever-solid government securities (G) fund grew 0.45 percent, while the S Fund, which invests in the stocks of small and mid-size companies, rose 0.37 percent.

The C Fund, which invests in common stocks and tracks Standard & Poor's 500 Index, eked out a modest 0.07 percent increase.

As their underlying funds grew, so did the TSP's new life-cycle funds. The L funds blend the stand-alone funds based on expected retirement dates, with the mix automatically becoming more conservative as participants near that date.

The L 2040 Fund, designed for participants planning to retire around 2040, grew 1.32 percent, largely boosted by its 25 percent allocation in the I Fund. The growth was tempered by a 42 percent allocation in the C Fund, however.

L 2030 grew 1.22 percent, the 2020 gained 1.11 percent, the 2010 increased 0.93 percent and the L Income Fund -- intended for employee set to retire in the near future -- grew 0.59 percent. Those figures are in keeping with the more aggressive nature of the funds for participants with later retirement dates.

For all of 2005, the I Fund's 13.63 percent increase led the pack, followed by the S Fund with 10.45 percent, the C Fund with 4.96 percent, the G Fund with 4.49 percent and finally the F Fund with 2.40 percent.

December's performance follows gains in November. That month saw the largest growth in the S Fund, which grew 4.72 percent, followed closely by the C Fund, which was up 3.75 percent. October was a losing month for the TSP. The G Fund had a 0.36 percent gain, but every other fund lost ground.