Who Really Powered XLK’s Return?

The tech fund’s impressive return looks broad, but a closer look reveals the heavy lifting was done by just a few of its holdings.

Among the 50 largest holdings in the State Street Technology Select Sector SPDR ETF (XLK), 38 rose over the past year while 12 fell. That positive tilt helped the fund deliver a +60.7% return. But if you own this fund, you should know that this gain wasn’t an even, all-boats-lifted story. The real work was done in a very concentrated way.

The Outlier That Did The Lifting
The single biggest contributor to the fund’s return was SanDisk (SNDK). While it makes up just 1.9% of the fund, the stock returned +4781% over the past year. Another key driver was Micron Technology (MU), which makes up 7.3% of the fund and returned +882.4%. These results did much of the heavy lifting for the entire portfolio. On the other side of the ledger, the biggest drag on the fund was Microsoft (MSFT). Being a large position, and falling over the past year, it weighed on the fund’s overall performance.

A Few Winners, A Lot of Spectators
This dynamic created a significant concentration in the fund’s results. In fact, the five biggest contributors produced about 73% of the combined gains from the holdings measured. While the fund holds 74 positions in total, its fate over the last year was largely decided by a handful of them. The median holding among the top 50 returned a strong +73.6%, but the fund’s overall return shows how a few exceptional performers can pull up the average, while significant drags can weigh it down.

What This Means For Your Diversified Tech Fund
If you own XLK, understanding this concentration is key. You own a fund designed to replicate the investment performance of the Technology Select Sector Index, and the performance you experienced was less about the 74 companies inside and more about the fortunes of a few specific names. This isn’t a flaw; it’s a feature of how many market-weighted indexes work. The key takeaway is that your exposure is narrower than the holdings count might suggest. Knowing that the fund’s return was driven by a few key stocks helps you understand what you truly own and what to watch. For instance, keeping an eye on top holdings like Nvidia (NVDA), the fund’s largest position at 13.2%, is a practical way to stay aware of where your risk and potential return are most concentrated.

Which Funds Are Genuinely Diversified?

XLK’s gains leaned on a handful of names, so your real exposure is more concentrated than the holdings count suggests. Two funds with the same label can carry very different concentrations, and most buyers never line them up. Our ETF Valuation and Performance Scorecard does exactly that for the full equity universe, sorting by risk-adjusted return and flagging how much of each fund sits in its largest holdings.

If you would rather not weigh it all yourself, the Trefis High Quality (HQ) Portfolio applies the same discipline a level deeper, with 30 individually screened names, rule-based re-balancing, and a record of outpacing a benchmark that combines all major indices – the S&P 500, S&P Mid-cap, and Russell 2000.