In 2014, the United States ranked 41st in the world in life expectancy, with an average American expected to live to age 78. But, like most averages, that doesn't paint the whole picture. Life expectancy is more like Norway's in some parts of the country and more like Kazakhstan's in others.

That's why it's more useful to look at it county by county. Here's how life expectancy in U.S. counties compare to averages around the world.

Data: World Bank, Institute for Health Metrics and Evaluation; Chart: Lazaro Gamio and Naema Ahmed / Axios

The big takeaways:

• Broadly, counties in the South have lower average life expectancies, while the coasts and the upper Midwest score higher.
• Oglala Lakota County, South Dakota has the lowest life expectancy in the country at 66 years. Summit County, Colorado has the highest at 86 years.
• Japan, Spain, Switzerland and Italy have the highest average life expectancy in the world at 83 years.
• Only four U.S. counties surpass 83 — three of them are in Colorado and the other is in North Dakota.

The data: Global life expectancy stats were published by The World Bank. The U.S. county level stats are from the Institute for Health Metrics and Evaluation.

Keep in mind: We're comparing life expectancy of U.S. counties to the averages of whole countries — which have their own regional differences, too.