The Illinois Department of Transportation (IDOT) purchased access to precise geolocation data about over 40% of the state’s population from Safegraph, the controversial data broker recently banned from Google’s app store. In an agreement signed in January 2019, IDOT paid $49,500 for access to two years’ worth of raw location data. The dataset consisted of over 50 million “pings” per day from over 5 million monthly-active users.