Mine actually had some ridiculous number as well the last time I checked-- YTD for 2020 it was somewhere between $1500 and $2000. I have three AUs but they are all extended family members so I generally know their travel plans-- I would estimate combined they've used maybe 6 entries this year (and none myself). Even accepting a starting value of $99 per PP card holder, it wouldn't be anywhere close to the number on the statement, so I just assumed it may have been an error on Citi's part.
On my statement this month, the number has changed to $180. The footnote under it reads, "Airport Lounge access is based on a complimentary membership fee of $99 and $27 fee charged per person, per visit." With three AUs, the numbers only make sense if it's accounting for a single $99 membership fee (so not including the AUs) and 3 visits. Not sure the numbers match what was actually used this year but oh well.