The Leaderboard is a separate feature that is irrelevant to the contests and contains various widgets that show your team's activity during a certain period and other achievements.
You can select the time period you want to view.
You can also select the metric you want to view.
Please note that the first widget displays the Top-10 leaders only and cannot be adjusted to show more members.
Here in a video below, you can learn more about the ''Stats'' section.