I took at look at the information in my user profile, and it appears to be missing some things.
The list of accounts shows eight accounts with a total of 69 questions and 19 answers. But the list of "activity > posts" shows 71 questions and 19 answers. The two additional questions are one each in two meta communities:
Are those communities not considered to be accounts (even though Meta Stack Exchange is an account), so that questions posted in them are excluded on purpose from the count of questions on the "accounts" tab of the profile?