It's hard to count ballots before you've counted them. I'd imagine the way the estimates work is "here's a 80 pound sack of ballots, each ballot weighs x ounces

It's hard to count ballots before you've counted them. I'd imagine the way the estimates work is "here's a 80 pound sack of ballots, each ballot weighs x ounces so we have about 80*16/x ballots. Plus more ballots are still coming in