The Thrift Savings Plan had a bleak December, with several funds in the red, according to the latest data from the Federal Retirement Thrift Investment Board.

The C Fund, invested in common stocks, fell 0.24 percent in December, while the international (I) fund tumbled 4.13 percent last month. In addition, all the lifecycle (L) funds posted negative returns.

December’s returns were a big contrast from November, when all the funds were in the black. Three funds experienced boosts last month: the F Fund, invested in fixed income bonds was up 0.21 percent and the S Fund, invested in small and midsize companies, increased 0.99 percent. The typically stable government securities (G) fund rose 0.18 percent in December.

The plan’s lifecycle offerings -- which move participants to a more conservative mix of investments as they near retirement – all fell last month. L Income, for those who have already started withdrawing money, dropped 0.04 percent for the month; L 2020 decreased 0.50 percent; L 2030 fell 0.67 percent; L 2040 tumbled 0.76 percent; and L 2050 dropped 0.94 percent.

President Obama last month signed into law the bipartisan Smart Savings Act, which changes the default enrollment fund in the Thrift Savings Plan for new hires from the safe but slow-growth G Fund to the more diverse, age-appropriate lifecycle funds. The law only applies to new federal employees who are auto-enrolled in the TSP. It does not affect TSP participants who are currently auto-enrolled. The board has to issue rules on implementation before the changes take effect. That likely will happen in October 2015.

Despite December’s largely lackluster returns, all the TSP offerings except the I Fund, were up for the whole year by the end of 2014. The C Fund performed the best, increasing an overall 13.78 percent during the year. The S Fund grew 7.80 percent during 2014, while the F Fund rose 6.73 percent and the G Fund increased 2.31 percent for the year.

The lifecycle funds were in the black overall for 2014. L Income was up 3.77 percent, L 2020 gained 5.06 percent, L 2030 increased 5.74 percent, L 2040 grew 6.22 percent, and L 2050 was up 6.37 percent.

The I Fund dropped 5.27 percent over the last 12 months.

(Image via baranq/Shutterstock.com)