Exactly. You shouldn't make too much out of the numbers given for one province; people are a bit mobile these days. Adding the attendance for the country after all the conventions have been held, gives a better picture. Over here, total attendance is always higher than the average number of publishers. Some visit two conventions, but on the other hand some live on such remote places or are aged / have health problems and no not attend. If that roughly would even each other out, then a higher attendance than average publishers is what I "feel" to be correct by own observation, as relatives, interested, a neighbour or two also attend.
As always, making worldwide conclusions based on a limited area or a limited time period is risky business. "Two youths committed suicide in my congregation = majority of JW youths commit suicide" .......... no no. "Three JWs in my area were admitted to mental hospital = most JWs are mentally ill" ....... no no. Extrapolation and intrapolation - risky business.