the snapshots provided in the year in review (ex. https://www.inaturalist.org/stats/2023/) seem to include only observations created during that year.
i’m talking more about a snapshot at a point in time that includes all observations at that time. here’s a post where i compared a couple of snapshots i captured at different points in time: https://forum.inaturalist.org/t/needs-id-pile-and-identifications/26904/4.
i’m sure there’s more to it, but this could explain part of the issue. if you zoom in on the RG to V map, the Boston core (on the right in the screenshot below) is very red, indicating a high RG to V ratio, but some of the blue spots to the west (on the left of the screenshot) with low ratio seem to be college campuses:
