Looks like E23 should be "72.71%" instead of "7271%" and G31 should be "95.72%" instead of "96.72%".
(no I didn't manually check every cell...I used math to verify the Combined::Renter::Combined percentages checked out as a set, which only identified 2 incongruent sets)
(...further down the math rabbit hole...)
I applied that consistency check to the average sets Len provided as well and BWV (5.9% off), BCV (1.43% off), VRB (1.98% off), HHI (1.68% off), and maaaaybe SSR (0.58% off) had set mismatches in the average sets. This implies that denominators were not the same across all months. Except for SSR, this aligns with refurbed resorts.
At least the errors were all on the low-side, implying there was some removed denominator inventory from some months (and not added inventory, which would be bizarre).
(...further still down the math rabbit hole...)
To use an extreme example to show error directionality, let's say a resort has 6 months of 1000 rooms in inventory and 6 months of 100-room in inventory.
If, during the 1000-room months, occupancy was at 95% and during the 100-room months occupancy was 55%, then the 'average set' calculation (which does not know denominators), would show a 75% average occupancy ((6 x 95 + 6 x 55) / 12). But the actual occupancy across the year would be 91.36% ((950 x 6 + 55 x 6) / (1000 x 6 + 100 x 6)).
(...further down the math rabbit hole: tokyo drift...)
I actually simulated the above 1000-room + 95% and 100-room + 55% scenario with 90/50 spltis during rich months and 50/10 splits during lean months, and the error across the year, 4.0%, is actually lower than BWV's 5.91%.
I'm not inclined to keep digging, but it seems that BWV had both a lot of inventory removed from the denominator and also didn't fill that limited inventory during its refurb. Crikey.
EDIT: (...jk, I totally went further down the math rabbit hole and now The Rock is here?...)
Upon further examination, cash booking percentages appear to be the main lever here for causing errors (a denominator mismatch is not even required). For example, I can do a 94/10 (94.6% total) paired with 30/50 (65% total) and get a negative error here.
There's probably a very good math reason that's not intuitive to me that explains this (beyond 'don't average averages'), but essentially the cash booking ratio is ridiculously overpowered in influencing the error comparing average of months. BWV's 5.91% being greater than my 1000::100 ratio example does not mean that BWV's denominator inventory was less than 10% of normal, it just means my example wasn't representative.
BWV's cash booking occupancy % during non-refurb months was excellent and simulating a 85/85 type of situation (97.75% total) with the original 50/10 (55% total) creates a bigger mismatch than BWV's actuals.