Extra Cloud Storage Consumed = Total Storage - (Mailbox Storage + VM Storage). Useful when obtaining extra cloud storage consumed (GB). Product usage you can use in the Gradient MSP billing module. divide( subtract( to_number(slice_string(to_string(Usages[].usages[?usage_name == 'total_storage'].value || '0'), 2, -2 ) || '0'), subtract( to_number(slice_string(to_string(Usages[].usages[?usage_name == 'mailbox_storage'].value || '0'), 2, -2 ) || '0'), multiply( to_number(slice_string(to_string(Usages[].usages[?usage_name == 'vm_storage'].value || '0'), 2, -2 ) || '0'), to_number('-1') ) ) ), to_number('1000') )