As of today, there are 106 Cardinal Electors out of 179 total living Cardinals.
In the month of September, three more Cardinals will turn 80 and lose their vote. An additional Cardinal loses their vote in each of October and November.
By mid-November, the Cardinal Elector count will be down to 101.
From there, the number is stable until late January, then in a period of 4 weeks, 4 more Cardinals turn 80.
A List of Cardinal Electors by Age.