For the second year in a row, the life expectancy of Americans got shorter.

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According to the latest report from the Centers for Disease Control and Prevention in Atlanta, the overall life expectancy in the U.S. was 78.6 years, down .1 from the previous year. Men can expect to live 76.1 years, down from 76.3. Women held steady at 81.1 years.

During the 20th century, advances in medications and other treatments were responsible for dramatic increases in how long people lived. But deaths from drug overdoses, chronic liver disease, suicide, Alzheimer's and blood infections (septicemia) have all gone up, resulting in a shortened average life span.

Heart disease and cancer still kill most Americans, but they weren't the reason people are dying younger. In fact, deaths from heart disease have been declining. Between 2006 and 2016, however, death rates from drug overdoses increased 72 percent and suicides increased 23 percent.

So who lives longest? According to the report, Hispanics had the highest life expectancy at 81.8 years. Non-Hispanic whites were next, with 78.5 years, followed by non-Hispanic blacks, with 74.8 years.

Where you live can also affect how long you can expect to live.

Areas in the bottom 25 percent of the report had four things in common: Most of the people were less educated, low income and predominantly black, and they were in the South.

The Robert Wood Johnson Foundation, which worked with the CDC on the report, created a calculator to determine the life expectancy of an area.

The average life span for Georgians, according to the calculator, was 77.40 years. If you live in Gwinnett County, though, you get an extra 3.18 years. Cobb County residents are looking at 80.08 years on Earth, but those in DeKalb County get only 79.14.

The area with the lowest life expectancy in the U.S. was Stilwell, Oklahoma, where people averaged 56.3 years. Where do people live longest? Chatham, North Carolina. Residents of this higher-income area could expect to be around until they reach 97.5 years old.