I don't have hard data but I have been following cases for about a year now. There's little over 1k+ cases in January and now they've started processing February. Same thing happened with December, November, September and so forth. Velocity of January will go down significantly and the main focus will be February in coming days and weeks. Processing velocity change happens at 1k mark for some reason that's the rule of thumb I've been using and it has been pretty accurate so far.
For the cases of November: https://docs.google.com/spreadsheets/u/2/d/1rVa_Eln8k9jbGkomGIRkKSIsyoCVp8gab2wwxXu1Aug/htmlview?fbclid=IwAR2ciGHqny6OnuLBbwajpr7cOB9fE0QPlb3s3Y6idh4NOh4ApWwliQm9F2A&mibextid=Zxz2cZ#. You can see the tracking data here. There were total 3496 cases. USCIS started seriously processing since
Jan 9 - Jan 16: 110 cases
Jan 17 - Jan 20: 236 cases
Jan 23- Jan 28: 540 cases
Jan 30 - Feb 4: 725 cases
Feb 6 - Feb 11: 567 cases
Feb 13 - Feb 18: 401 cases
At this point they hit that 1k mark remaining for November and they swiftly moved their focus to December. December was having roughly 400 cases/ week at this point and November was having 200/week or less and it has slowed down ever seen.