Looking at the members list and looking at the More Stats page, the result certainly do not agree imho. I suspect the stats are wrong, but I have no idea why.
Could be a simple as a mistake in an SQL statement, or could be bug in the actual software, or any number of other things, unlikely be be unix time wrap as that is not due to 2038 and if it was a simple signed/unsigned problem would have been seen before 50 years had passed.