Memory Allocation Limit and missing memory

Hi folks,

We have 1TB of memory however only paid for licensing of 576GB.  This is value set in configuration parameter global_allocation_limit = 576.  Yet when we look at ADMIN CONSOLE / OVERVIEW - SAP HANA Used memory graph it shows Used/Peak Used/Allocation Limit and this is showing just 562.50 GB as the maximum allocation limit (the right-most number that displays on the graph).  The question is where did this 14GB disappear to?

Thanks!

-Patrick