Decreasing Homicide Clearance Rates in the United States

There are currently more than 226,000 homicide cases that have not been solved since 1976. Even with the number of homicides being committed in declining, the portion of unsolved cases each year is increasing. This data visualization project explores homicide clearance rates in the United States over the years and allows for further analysis of the types of cases that are not being solved. Homicides where the victim is a stranger to the offender are not solved as often as cases where the victim and offender know each other.

This data comes from the Murder Accountability Project, an outgrowth of a 2010 national reporting project conducted by the the E.W. Scripps Co. The computer algorithm that identifies serial killings within FBI computer files was developed as part of that project.

MAP provides a mostly complete list of all reported homicide cases in the United States from 1976-2017 in a CSV file. To create these visualizations, I downloaded that file and used Excel to clean the data.

I simplified the categories in the weapon, relationship and age fields to fit similar values into just one category (e.g. combining all gun/firearm categories into one).

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Data was cleaned for the following visualization using Excel. I calculated the percentage of cases that were solved each year for each state and removed Hawaii and Alaska so the map covers only the continental United States.

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