Jim at
https://bigblue1840-1940.blogspot.com/ uses Steiner pages which cover 1840-1940 plus he includes British Commonwealth issues to 1952 and reports a count of 83,458 spaces in the pages of which 950 are for stamps for the United States.
I use the current Scott 1A1-1B2 plus other parts pages and, currently, show 34,598 issues for the Part I set, 16,850 for Part II, 13,941 for Part III, 8,623 for Part IV, and 11,694 for Part V (through 1963) for a total of 85,706 issues in the International pages. My counts include the counts of the cut squares, etc. that are part of the 1A1-1B2, Part II, Part III, Part IV, and Part V (through 1963) pages whereas Jim excludes those issues from his Steiner based pages. I have had several corrections of miscounts in my original issues counts that I have encountered as progress continues on the collection. Currently I am at 49.28% complete for 1840-1963 and 49.07% complete for 1840-1940. All stamps in the albums are mint. The USA portion is currently at 580 of 717 issues with 14 missing back of the book issues, i.e. Scott #'s that start with a alphabetic character.