On the Leaderboards you can see 'Yesterday' as an option, but that only counts the last 24 hours.
The next option is Last week, but that seems to be the previous week - in other words, when I look today (Wendesday) the table is empty as no-one was tipping last week.
What appears to be missing is the option to see what has happened this week: people have been tipping since Monday yet I can only see results for Yesterday (Tuesday). I can't see results for the this week in full.