The gap in life expectancy between U.S. whites and blacks has narrowed considerably as African Americans make progress against major killers such as heart disease, cancer and HIV, the Centers for Disease Control and Prevention reported Friday.

Average life expectancy for blacks was 5.9 years less than for whites in 1999. That gap shrank to 3.6 years in 2013, the National Center for Health Statistics reported, as longevity rates for African Americans increased faster than they did for whites.

The gains would have been even larger "if not for increases in death rates for the black population [from] aortic aneurysm, Alzheimer's disease and maternal conditions."

The news comes in the same week as a separate report by Princeton researchers showed a startling increase in the death rate for middle-aged whites, most notably men and women aged 45-54 with high school educations or less.

Overall, whites could expect to live 79.1 years at birth in 2013, a steady 2.3 percent improvement since 1999. Men could expect to live 76.7 years and women 81.4 years.

Black life expectancy rose to 75.5 years, a solid 5.7 percent gain over the 14-year period. Men could expect to live 72.3 years and women 78.4 years, according to the report.

During that time, blacks made notable progress in rates of heart disease, cancer, HIV, unintentional injuries, and perinatal conditions, which together accounted for 59 percent of the decline in the black-white life expectancy gap, as you can see below. Greater progress against death from heart disease and HIV in particular helped African Americans catch up to whites.

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