How vcops5 calculates the number of remaining available VMs in capacity remaining badge?

I had a datastore4(1497 GB) and 3 VMs (power on) on it, the used space of them were 221GB, 139GB and 15.04GB.

I click datastore4 object on the left hand side of the /vcops-vsphere web page.

The Capacity Remaining showed "DEPLOYED 3 VMs, POWER ON 3VMs, and 8 More VMs".

Then I created another VM (power on) on datastore4 which used space was 34GB.

24 hours later, the Capacity Remaining showed "DEPLOYED 3 VMs, POWER ON 3VMs, and 9 More VMs."

The information about deployed and power on VMs was not correct (should be 4), and and the remaining available VM number increased(8 -->9.

Thus , I was wondering when the object is datastore, how vcops5 calculates the number of remaining available VMs in capacity remaining badge?

Thanks in advance.