The Thrift Savings Plan currently offers ten investment funds. Five are US and international stock and bond index funds: they replicate the performance of broad market indexes. The other five TSP funds, the Lifecycle Funds, are professionally managed portfolios which consist of a specific target allocation of the 5 individual TSP index funds.
The TSP Funds contain a diversified portfolio of thousands of individual stocks and bonds. Investing passively in index funds such as these is generally considered to be a good retirement savings strategy. The alternative is for you or an investment manager to actively pick individual stocks and bonds to buy and sell. Apart from being impractical for individual investors, this latter strategy usually also leads to inferior investment results: research has shown that most professional active fund managers under-perform a passively managed portfolio of index funds such as the TSP funds.
Here's a summary of the five primary TSP Funds:
- The G Fund is invested in US Treasury securities which are guaranteed by the US government. The nice thing about this fund is that it's practically risk free (your investment is guaranteed not to lose any money), and yet the interest rate is substantially higher than what you would earn in other safe investments like bank savings accounts, certificates of deposit, or money market funds. If you are very risk-averse, this is definitely the place to park your savings.
- The F Fund is a bond index fund, invested in high-grade US government and corporate bonds. Its performance is very similar to the private sector iShares Barclays Aggregate Bond ETF.
- The C Fund is a US stock index fund that mirrors the returns of the S&P 500 Index, which consists of large US corporations. Its returns are essentially the same as the SPDR S&P 500 ETF.
- The S Fund is invested in the stocks of small to medium-sized US companies. It's designed to complement the C Fund, so if you invest in both, you basically own shares in almost all US stocks. There aren't a lot of index funds that track these companies, but if you own both the TSP S Fund and C Fund, then your investment returns will correlate closely to a broad US stock market index fund like the Vanguard Total Stock Market ETF.
- The I Fund is allocated to international stocks. It allows you to diversify your portfolio by investing in the stocks of companies in more than 20 developed countries in Europe, Australia, and Asia. There are several private sector equivalents to the I Fund, including the iShares MSCI EAFE Index Fund.
The other five funds, the TSP Lifecycle Funds, consist of professionally managed investment portfolios designed to meet investment objectives for a specific target date (the date on which you plan to begin withdrawing your money). The L Fund assets are invested in the individual TSP funds (the G, F, C, I, and S Fund) according to a target portfolio allocation which is adjusted every 3 months. The target allocation starts out risky, with a large percentage of stock funds such as the C, S, and I Fund. As the target date approaches, each L Fund becomes gradually more conservative, by shifting a larger portion of your assets into bonds such as the F Fund and G Fund. This investment strategy assumes that, while you're still a long time away from retirement, you're willing to take on greater risks in order to increase your potential investment returns. Also, while you're still at the start of your career, you have a longer period to recover from potential investment losses, considering that you'll continue to make monthly contributions to your account for many years.
Depending on your personal circumstances and target retirement date, you choose one of the five L Funds: L Income, L 2020, L 2030, L 2040 or L 2050 Fund. The L Income Fund is the most conservative asset mix and assumes that you've already started withdrawing your savings. The L 2050 Fund is the most aggressive allocation, currently 90% stocks and 10% bonds.
Benefits and Disadvantages of Investing in the TSP Funds
Many investment advisors recommend that for long-term retirement savings, you buy and hold a low-cost, broadly diversified portfolio of domestic and international stock and bond index funds. With the available TSP investment funds, you can do an OK job at this. By investing in all five individual TSP funds, or in one of the Lifecycle Funds, you'll have a decent portfolio, with an ownership share in thousands of US and international stocks and US bonds. And the TSP funds have extremely low annual expense ratios, several times lower than comparable private sector mutual funds and ETFs, keeping more of your money working for you.
So what's wrong with the list of currently available TSP investment choices? Some investors want to own Emerging Markets stocks (in addition to the Developed Markets international stocks in the TSP I Fund). Or an allocation to real estate (REITs), or inflation-protected securities (such as TIPS). And some would even like access to more exotic investments like international bonds, high-yield bonds, and other hedges against inflation (commodities and precious metals like gold and silver). Professional advisors would differ on how suitable these investments are. Most would agree that TIPS are a good idea, and for more risk-tolerant investors, perhaps a small allocation to REITs and Emerging Markets stocks.
One great benefit of investing in an L Fund is simplicity: it's a "set it and forget it" investment plan. You choose an L Fund, determine your monthly contributions, and the fund administrators take care of everything else: regular portfolio rebalancing, and gradually adjusting the asset allocation as you approach retirement. But there are also a few downsides. First, the L Funds with the longer time horizons are fairly risky allocations (for example, currently 90% stocks and 10% bonds for the L 2050 fund), and you should make sure that you can stomach the inevitable volatility as a result of owning a portfolio dominated by stocks. If you've owned stocks for the past decade then you already know this: it can be quite a bumpy ride. Also, some investors want more control over their exact portfolio components, when to rebalance, and how soon to start shifting the allocation to a more conservative asset mix as they approach their planned retirement date. Some investors also prefer a tactical asset allocation, shifting their mix based on asset class trends, economic circumstances or other criteria. Owning a portfolio of the individual TSP funds will work better for these investors.