NEW YORK (AP) - The stock market slumped to its worst loss since August, giving back some of the big gains it has posted since the beginning of the year.
Health care companies were by far the biggest losers on Tuesday.
Insurers, drugmakers and distributors slumped following news that Amazon was teaming up with JPMorgan Chase and Berkshire Hathaway on a health care venture.
CVS Health sank 4.1 percent and UnitedHealth Group dropped 4.3 percent.
The Standard & Poor's 500 index fell 31 points, or 1.1 percent, to 2,822.
The Dow Jones industrial average slid 362 points, or 1.4 percent, to 26,076. The Nasdaq lost 64 points, or 0.9 percent, to 7,402.
Bond prices continued to fall. The yield on the 10-year Treasury rose to 2.72 percent, its highest level in almost four years.