Changes In Ore Prospecting Rates?

hello good people on lordaeron!
last year (2023) i prospected 245 stack of saronite ore (4900 saronite in total) and the result was 2525 uncommon gem(dark jade, shadow crystal, ....) and 217 rare gem (scarlet ruby, sky sapphire , ...)
recently i had a feeling that the prospecting is not profitable as it was before so i decided to update my data and here is the new results :
i prospected 300 stack of saronite ore (6000 saronite) and uncommen gems are 1480 and rare gems are 281!
thats about 40% decrease in uncommon gem drop rate and about 30% increase in drop rate of rare gems!

HERE is my question:
when did the drop rates changed? is the data about the drop rated posted anywhere ?if its posted somewhere where it can be found?


P.S: ore prospecting data here is totally different with what is posted on wowhead.
P.S 2: the data is belonged to horde faction

update 1 : i done the same thing on ally side with 152 stacks of saronite the results are : 784 uncommon and 123 rare