Admin level users has access to monitor storage usage through the Storage control panel.
Enter the Control Panels and click on the Storage icon . In the Storage control panel you can see how much storage you have used and find instructions on how to release or buy additional storage.
The storage indicator
In the bottom of your browser window Admin level users will find the Storage indicator. When everything is fine the storage indicator is green . When you have used 75% of your total storage the storage indicator will turn Orange . And when you have used 90% of your total storage space it will turn red . When you have used more than 100% of your total storage you will not be allowed to upload more files until you either release storage space or buy additional storage.
NOTICE: If you hold your mouse over the Storage indicator, you can quickly see how much storage you have used and how much you got left.