The short version

Thursday was a good day for most TSP funds, and the S Fund did the heavy lifting. It gained 1.13%, the only fund to clear the 1% mark. The C Fund added 0.42%, the F Fund rose 0.12%, and the G Fund did what it always does, edging up 0.01%. The I Fund was the lone decliner, off 0.05%.

How the individual TSP funds did

S Fund (+1.13%, $115.5992). It tracks the Dow Jones U.S. Completion index, which covers the U.S. stocks outside the S&P 500. That makes it small and mid-sized companies. Over five days it is up 1.57%, and it sits at 13.7% for the year. A move this size is worth noting, but one strong day does not change the bigger picture.

C Fund (+0.42%, $121.9526). This one follows the S&P 500, which gained 0.41%. The two lined up almost exactly, as they should. The C Fund is up 0.31% over five days and 11.12% year to date.

I Fund (-0.05%, $64.7097). It follows MSCI ACWI ex-US ex-China, so it holds international stocks outside China. The slight dip is basically flat. Even so, it has gained 0.67% over five days and leads every individual fund year to date at 15.49%.

F Fund (+0.12%, $20.9601). It tracks the Bloomberg U.S. Aggregate bond index. Yields eased a bit, and bond prices move opposite to yields, so a small gain fits. The fund is up just 0.48% this year.

G Fund (+0.01%, $19.9497). It earns a Treasury-based rate and has no price swings. It is up 1.82% year to date.

L Funds

Every L Fund finished higher, and the pattern is orderly. L Income gained 0.11%, L 2030 rose 0.20%, and L 2040 added 0.26%. The L 2055 through L 2075 funds all gained 0.34% and show the same 12.93% year-to-date figure. That is what you would expect, since these funds blend the five core funds and the later-dated ones hold more stock. On a day when stock funds rose and the bond and G funds barely moved, the funds with more equity gained more.

What moved IRA-style funds

The index figures below are from the prior session close. The S&P 500 gained 0.41% to 7,584.31, matching the C Fund. The Dow was the standout, up 1.73% to 51,561.93. The Nasdaq Composite slipped 0.09% to 26,830.961.

A strong Dow alongside a soft Nasdaq suggests the gains were spread beyond the biggest technology names. The S Fund's jump fits that picture, though the data here does not tell us the cause.

Among the ETFs many IRA savers own, the Vanguard Total Stock Market ETF (VTI) rose 0.47% to $373.38. The Vanguard Total International Stock ETF (VXUS) gained 0.17% to $86.25, while the TSP's I Fund slipped slightly. That gap is not alarming. VXUS holds China and emerging markets, which the I Fund's benchmark excludes, and the two can easily differ by a few tenths on a given day.

Bonds were quiet but positive. The Vanguard Total Bond Market ETF (BND) added 0.14% to $73.16. The 10-year Treasury yield dipped 0.31% to 4.477, which helps explain the small bond gains.

What it means for your plan

A day like this is pleasant, not meaningful. A 1.13% gain in the S Fund can be reversed in a session or two, and a 0.05% dip in the I Fund is noise. What matters more is whether your mix of stocks, bonds and G Fund still matches your timeline and your comfort with ups and downs. Year-to-date figures are useful for context, but they are a snapshot, not a forecast.

If you contribute every paycheck, you are buying at whatever price shows up each period, which is the point of the routine. Check in on your allocation on a schedule you set, not because of one headline day. This recap is general information, not personal advice.