Every time the stats on your account page update it is for a full 24 hour period. It may be 1pm to 1pm or 8am to 8am.
If you scroll down to the bottom of your account/stats page - look for the minutes. It usually updates somewhere between 60 - 75 minutes. The new stats are shown when it updates.
Therefore, it may show lower or higher views for that particular full 24 hour period.
I hope that made sense :)