Well, every month and quarter USCIS got to report the statistics to Congress on all applications including numbers submitted, approved, denied, pending, and all. You may find the historical reports here - https://www.uscis.gov/tools/reports-and-studies/immigration-and-citizenship-data?topic_id[]=33692&ddt_mon=1&ddt_yr=2025&query=&items_per_page=50
I am attaching the one Dec 2024 one. The total N-400 application submitted in Dec 2024 was: 74910.
Also, note that casestatusext only tracks IOE09######## cases which are paper filed. The online filing case number starts with IOE9. It is extremely difficult to track the IOE9######### as they are randomly assigned.
appropriation_requirement_december_2024.pdf