Population numbers in registry sets

Goldminers

In all the registry sets there are 4 columns of populations:
PCGS# POP
PCGS# POP HIGHER
PCGS POP
PCGS POP HIGHER

It seems like there may be a database formula glitch in some of these numbers or maybe I just don't understand how they are defined. This is for basically all sets.

Checking a Top 100 Modern Coins Set for example:

The 1999-W $10 eagle unfinished proof dies MS PCGS coin #99942 that has a MS69, it shows 1,468 with 17 higher in both columns. For the base coin pops these seem to be the correct numbers, but for the coin including varieties If you go to CoinFacts and the population report for the #99942 it shows 1,545 MS69's and 23 MS70's.

Should the last two pop columns include all the varieties in the pop numbers for that coin? Otherwise it just seems like it is not any different than the first two columns.

DIMEMAN

I believe that is for series that have a Non FB and a FB designation etc. The first two columns are for actual coin in the set line while the other two could be for the numbers for coin with designations. Coins with no designators would always be the same.

Goldminers

@DIMEMAN said:
I believe that is for series that have a Non FB and a FB designation etc. The first two columns are for actual coin in the set line while the other two could be for the numbers for coin with designations. Coins with no designators would always be the same.

Thanks. it may be as you say. There are lots of "designators": FB, steps, PL, DMPL, burnished, Mercanti, David Hall or other labels, First Strike, RB, RD, BN. CAC, etc , etc.

To me those are all "varieties or designations?". But if you are correct which is likely, for most sets it seems there should be totals or additional columns that show total pop of that grade in any possible designation or variety, and total pop higher than that specific coin variation grade? It is all getting complicated, but ultimately grade in any designation matters to many people also.