"Although local jails are increasingly recognized as the “front door” to mass incarceration, justice system stakeholders and others historically have not had access to the necessary data to understand how their jail is being used and how it compares with others. To address this issue, Vera researchers developed a data tool that includes current and historical jail incarceration rates for every U.S. county. The data revealed that, since 1970, the number of people held in jail has increased from 157,000 to 690,000 in 2014—a more than four-fold increase nationwide, with growth rates highest in the smallest counties. This data also reveals wide variation in incarceration rates and racial disparities among jurisdictions of similar size, highlighting that the number of people in jail is largely the result of policy choices. With this new information in hand, policymakers can begin to make choices that are better for their communities."