So far in 2015, the best-performing sector within the large-cap S&P 500 index has been health care. It has also held that positive momentum over the past 12 months as well, handily beating out both technology and consumer discretionary stocks during that span.
Meanwhile, the worst-performing sector in 2015 has been utilities, which has fallen off relatively sharply given concerns over rising interest rates. Utilities and other big dividend-paying stocks often see weakness when interest rates are expected to increase, because as rates rise, the relative attractiveness of heftier dividend yields diminishes.
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The market could see a change in sector leadership during the month of April, at least if recent history has anything to say about it. According to market data and analytics firm Kensho, over the last 10 years, April has been kinder to utilities investors than health care investors.
Among major S&P 500 sector-tracking exchange-traded funds, the Utilities Select Sector SPDR has managed to post an average April gain of 3.4 percent over the last decade, and has not had a losing month. In other words, the utilities ETF is riding a streak of 10 straight Aprils without a loss.
It's worth noting the study showed that the Financial Select Sector SPDR produced the best average April gain of 3.5 percent, but was positive just 70 percent of the time, compared to the unblemished 10-year run for utilities.
As for the notable underperforming broad-sector ETF, health-care stocks bring up the rear. Over the last 10 years, the Health Care Select Sector SPDR has managed to post an average gain of 1.4 percent during the month of April, but has only been positive half the time.
Compare those to the overall S&P 500, which is up an average 2.4 percent, and has posted a gain 80 percent of the time.
A list of other sector ETFs is posted below.
April performance over last 10 years
| Symbol | Name | Avg Return | % of Trades Positive |
| XLF | Financials | 3.53% | 70.00% |
| XLU | Utilities | 3.39% | 100.00% |
| XLE | Energy | 3.33% | 60.00% |
| XLI | Industrials | 3.13% | 70.00% |
| XLY | Cons. Disc. | 3.12% | 80.00% |
| S&P 500 | S&P 500 Index | 2.35% | 80.00% |
| XLB | Materials | 2.28% | 80.00% |
| XLK | Technology | 2.00% | 70.00% |
| XLP | Cons. Stap. | 1.73% | 70.00% |
| XLV | Health Care | 1.38% | 50.00% |
Source: Source: Kensho
So, for those traders looking for an excuse to lighten up on health care, the last decade worth of April performance data might give them the push they need. And the same goes for those who are looking for a reason to buy the recent dip in utility stocks.
Of course, the usual caveats apply ... past performance is not a guarantee of future performance.
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However, some traders who like using history as a guide may have found a reason to at least take another look at recent performance trends in health care and utility stocks ... at least for the month of April.
—CNBC's Gina Francolla contributed to this report.
Disclosure: NBCUniversal, parent of CNBC, is a minority investor in Kensho.