“After the election, they have workers who sit with barcode scanners and scan in the barcodes of everybody who voted. That process can take up to 45 days. “
http://www.wpr.org/wisconsin-absentee-voters-worried-ballots-didnt-count-results-tally
http://elections.wi.gov/node/4397
"But all absentee ballots were included in the results of the 2016 election, Reid Magney, state Elections Commission spokesman, said."
"After the election is over, municipal clerks go through the thousands of names of voters in the polling books and record them online, Magney said."
"After the election, they have workers who sit with barcode scanners and scan in the barcodes of everybody who voted," Magney said. "That process can take up to 45 days."
The longer process is updating the on-line database with data from the checklists that show who voted.
States also gather extensive statistics on absentee voting, since some of that information is required by the federal government.