A reddit researcher named Greenkappa1 tested more than 160 PokeStops to see if the item drop rates have changed significantly recently. As per his research, the average amount of Item dropped per Stop is the same (around 3.11), but the item chances have changed.
Pokestop Item Rates
Hello there! There are few posts in threads here and there that state, or otherwise assume, there was a reduction in the number of drops from Pokestops. Additionally, the objective was to collect data before any upcoming event to use as reference after the event if there is a perception of a change in drop rates.
160 Pokestops were spun with no stop hit more than twice in a dense urban area. Sufficient bag space was cleared and starting and ending quantities of items were recorded. Only two Pokemon were caught during the study (couldn’t pass up a Dratini and Grimer even in the interest of science) but adjustments were made for the items used. Egg slots were empty and 31 stops were spun to fill them – no further incubation took place so the study does reflect egg drops at all. The results include comparison to the previous referenced analysis of 3207 Pokestops.
|Item||Drop % December||Drop % August|
Average Item Drop per Pokestop
- December — 3.16 (Excluding 10 stop bonus)
- December – 3.52 (Including 10 stop bonus)
- August – 3.11
The study shows that overall drop rate per stop correlates to early data shortly after game release. Although there was a known adjustment to the ratio of potions, the overall drop rate is the same and there has not been a reduced drop rates from Pokestops.
tl;dr: There has not been a change in item drop rates from Pokestops.