The S&P 500 index had its best quarterly gain in four years, with health care as the standout sector.

Why it matters: Investors prioritized rosy corporate earnings over escalating trade tensions and rising interest rates, which many predicted would drive stocks down.

Health care and industrials were the top performing sectors.

• The technology sector was the third best performing sector, despite companies like Facebook's tumultuous three months.
• The materials sector, comprised of companies like United States Steel, was the loser.

The best performing stocks in the Dow Jones Industrial Average were Apple, Pfizer, and Nike.

• Intel, Chevron, and DowDupont were among the worst performing Dow stocks.