Shares of power producers rose as Treasury yields fell to multiyear lows, spurring demand for the defensive dividend-oriented sector.

The SPDR Select Sector Utilities exchange-traded fund, which tracks the utilities industry group of the S&P 500, is now up roughly 20% for the year to date.

The only subdivision of the stock market with comparable performance is the mega-cap tech niche.

The Roundhill Magnificent Seven exchange-traded fund is up about 32% for the year to date.

"It is not often - in either a bear or bull market - that the market's quintessential aggressive high-beta technology sector runs neck and neck with the market's poster child for defensive positioning - the windows & orphans utilities sector," said Jim Paulsen, a longtime Wall Street strategist who publishes an independent research newsletter.

Paulsen said the market's defensive bias was also reflected in the strength of gold futures.