The Census Bureau’s population counts make trends in household makeup easy to track. All you need are two things: an understanding of how the Census asks Americans about households and relationships, and where to find the right tables amid the haystack of tabulations. That’s what this post aims to help you with.

“Behind the Bloodshed: The Untold Story of America’s Mass Killings,” is a collaboration between the database team at USA Today and Gannett Digital’s interactive applications and design teams. We chatted with Anthony DeBarros of Gannett Digital, with input from colleagues Juan Thomassie and Destin Frasier, on how the project came together.