Ever wondered where the best places to live are as a Black American and why? Well, researchers at the Brookings Metro and the NAACP think they may have the answers.

This week, they co-launched the “Black Progress Index,” a tool for gauging which counties Black Americans are thriving in and what factors may be contributing to their success. The BPI looks at life expectancy for Black Americans per county as well as a host of “well-being” metrics their model shows increases life expectancy for Black Americans.

In order to do that, Andre Perry and his team sorted through a host of data points, including income, math proficiency, religiosity, gun deaths, and homeownership rates, to figure out what about a Black population leads to higher life-expectancy rates.

It’s not surprising that wealthier Black communities with higher Black homeownership rates like Loudoun and Fairfax County, Virginia, had higher life-expectancy rates than places like Bibb County, Alabama.

But, Perry’s team also discovered some more surprising findings. For example, they discovered that high-rates of Black religious participation actually drove down life-expectancy in a county regardless of income. And that having a greater distance between you and your friends on social media drove-up life expectancy.

The BPI’s findings in Washington, D.C., were also interesting. Compared to neighboring suburbs like Montgomery County, the life expectancy for Black Americans in D.C. is significantly lower. One thing to look at says Perry is the rate of homeownership rates versus median income. Although the median Black income is on the higher end, the home ownership rate is relatively low. Perry says this generally means that a smaller percentage of wealthier people who can afford homes are bringing-up the median income.

Perry and his team plan on using this metric for years to come to help cities and counties make necessary improvements to help Black communities thrive.