Maximum, Minimum and Average CPU & Memory usage per cluster

Hi,

I need to get Maximum, Minimum and Average CPU & Memory usage per cluster. For a specific amount of time. for example a week. Currently I am using this:

foreach($vmHost in Get-VMHost){
  $hoststat = "" | Select HostName, MemMax, MemAvg, MemMin, CPUMax, CPUAvg, CPUMin
  $hoststat.HostName = $vmHost.name

  $statcpu = Get-Stat -Entity ($vmHost)-start (get-date).AddDays(-7) -Finish (Get-Date)-MaxSamples 100 -stat cpu.usage.average
  $statmem = Get-Stat -Entity ($vmHost)-start (get-date).AddDays(-7) -Finish (Get-Date)-MaxSamples 100 -stat mem.usage.average

  $cpu = $statcpu | Measure-Object -Property value -Average -Maximum -Minimum
  $mem = $statmem | Measure-Object -Property value -Average -Maximum -Minimum

  $hoststat.CPUMax = $cpu.Maximum
  $hoststat.CPUAvg = $cpu.Average
  $hoststat.CPUMin = $cpu.Minimum
  $hoststat.MemMax = $mem.Maximum
  $hoststat.MemAvg = $mem.Average
  $hoststat.MemMin = $mem.Minimum
  $allhosts += $hoststat
}
$allhosts | Select HostName, MemMax, MemAvg, MemMin, CPUMax, CPUAvg, CPUMin | Export-Csv $outputfile -noTypeInformation

This though gives me the information I want, per host, not per cluster.

How can I get this information per cluster?

Thanks