If you open the "View Status" section, right below the bar of your current level is, you will see multiple icons in each week that has passed. Below are the meaning for each icon status:
You're Here shows in which week you are right now
Constant means that you stayed in the same position at that particular week
Pending means that your status for that particular week was still being reviewed. It could be due to your receipt was not yet validated. This icon will be changed once your receipt got accepted/rejected
Upgrade means that you were upgraded at that particular week. You are upgraded because you reached the minimum valid receipts needed to go to the next step
Downgrade means that you were downgraded at that particular week. You were downgraded because no valid receipt was found during that week.