When I attended regularly (1996 to 2002) the number baptised was around 15 to 40 at district conventions and 0 to 15 at circuit assemblies.
I doubt there is any way you can collect enough anecdotal information to provide any meaningful comparison with official figures. As others have pointed out, "total number of baptised JWs" is not a statistic that has ever been published anyway.
What are you trying to work out?
Are JW statistics generally reliable? Yes
Have they made some mistakes and is there some evidence of falsification? Yes
Nevertheless the official statistics are generally reliable.
In any case I would argue that the single most important statistic for giving a picture of growth, vibrancy, or decline over the long term is the number of congregations. And the great advantage of this statistic is that it's very hard or impossible for JWs to falsify since congregation meetings are individually listed publicly.