The voter records in this visualization come from two citywide voter history files, one from 2013 and one from 2018. New York voters are assigned a unique identifier at the time of registration called an EMSID. The two voter history files were joined on voter EMSID. Therefore, the only voters included in this project are those that were in both voter history files. The 2018 file has 4,604,801 records and 3,667,662 (79.6%) matched with the 2013 file. According to the 2018 file, 2,706,535 people voted in the 2016 election. 106,085 (3.9%) of these voters were registered to vote prior to the 2008 presidential election, but did not vote until the 2016 presidential election. The records are geocoded to current election districts, not 2016 vintage districts. Some of the election districts have been redrawn since 2016 and the election results for those districts are not available. The gender information supplied by the Board of Elections includes only binary (male or female) gender identification. Source: NYC Board of Elections via CUNY Center for Urban Research.