(CNN)For decades, nearly all Americans -- in every age and racial group -- have seen decreases in death rates. But in the last nearly 15 years, middle-aged white Americans have been left out, according to a study.
Death rates for white Americans ages 45 to 54 climbed half a percent each year between 1999 and 2013, researchers at Princeton University found using mortality data from the Centers for Disease Control and Prevention. In the previous two decades, the death rate for this group had dropped by 2% each year. Middle-aged blacks and Hispanics continued to see a 2% annual decline between 1999 and 2013.
"We have come to expect mortality rates in middle age to continue to decline, which they did throughout most of the 20th century...it was really a surprise to see a sustained period when mortality rates actually increased (among middle-aged white Americans)," said Anne Case, professor of economics and public affairs at Princeton University.
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