Nebraska’s centralized voter registration database changes every day — for a variety of reasons. From individuals changing addresses to people who have passed away, the Absentee Roster and Sign-in Registers for each election accurately identify the number of individuals voting in a particular election. These public records are available for public inspection and retained for twenty-two months following each election.
See Our Voter History Laws
https://nebraskalegislature.gov/laws/statutes.php?statute=32-330