Script to count PoweredOn VMs in multiple vCenters

I have a script that will give me the total count of Powered on VMs in each environment, but I would love for it to automatically add the values together and display an overall total, instead of exporting each vCenter's count to a CSV. 

For example, I'd like it to see total VC01=100, VC02=200, VC03=50, VC04=250, VC05=100.  Total = 700 Powered On VMs. 

Anyone have any suggestions? 

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# Build array for each vCenter with vDS switch

  $array = "vc01", "vc0e", "vc0e", "vc04", "vc05"

  for($count=0;$count -lt $array.length; $count++)

{

# Connect to All vCenter Servers, one at a time.

connect-viserver $array[$count]

# Get VM counts & export to CSV

Get-VMHost | Get-VM | where-object {$_.PowerState -eq "PoweredOn"}| Measure-Object | export-csv -notypeinformation c:\ben\vmware\$($array[$count])_vm_count.csv

# Disconnect from vCenter Servers

disconnect-viserver -confirm:$false

}

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Thanks in advance!