Based on dates in the merged ROM set I checked, there were 170 new/updated ROMs in MAME 0.263 (Feb 2024) and 90 for MAME 0.262 (Jan 2024). Those were from merged rom sets so every zip file has 1-20 individual ROMs inside
The denominator here is 14,566 so that's 0.6% to 1.1% per month which is substantially less than all. These would mostly be ROMs for machines that weren't previously supported, replacing high level emulation with low level emulation, new ROM dumps, and replacing bad dumps.
The denominator here is 14,566 so that's 0.6% to 1.1% per month which is substantially less than all. These would mostly be ROMs for machines that weren't previously supported, replacing high level emulation with low level emulation, new ROM dumps, and replacing bad dumps.