How long is my form taking?
USCIS publishes a range per form and per office. Both matter — the same form can differ by months depending on where it is being handled.
Forms decided at a local field office, where which office you are assigned to changes the answer by months.
I-829 — Petition by Investor to Remove Conditions on Permanent Resident Status
24 to 72.5 months (2 to 6 years)
Immigrant Investor Program Office
Estimated median
7 months
The published range is the slow tail, not the middle: USCIS's low figure is where about 80% of cases have finished and the high figure about 93%. So half of cases finish sooner than 7 months — three in four by 21.6, nine in ten by 67.7. An estimate from those two published anchors, not a figure USCIS publishes.
Ranges are as published by USCIS: the low figure is where about 80% of cases have finished and the high figure about 93%. Confirm on Check on USCIS's processing times page.