Yellowjacket colonies are annual and mostly die off each winter, with only mated queens overwintering to found new nests, so no comprehensive census tracks total colony or individual numbers across the many Vespula and Dolichovespula species and their ranges.
What would resolve this Standardized trapping and nest-density surveys repeated across regions and seasons for every yellowjacket species.
OpenEntomologyYellowjacket (Wikipedia)