virtualDisk stats

Please help me fix below...i get blank csv

$report = @()

Get-VM XP | %{

#virtualDisk.totalWriteLatency.average

#virtualDisk.totalReadLatency.average

#virtualDisk.numberReadAveraged.average

#virtualDisk.numberWriteAveraged.average

#virtualDisk.read.average

#virtualDisk.write.average

     $stats = Get-Stat -Entity $_ -Stat virtualDisk.totalWriteLatency.average,virtualDisk.totalReadLatency.average,virtualDisk.numberReadAveraged.average, virtualDisk.numberWriteAveraged.average, virtualDisk.read.average , virtualDisk.write.average  -Start (Get-Date).adddays(-1) -ErrorAction SilentlyContinue

     if($stats){

          $statsGrouped = $stats | Group-Object -Property MetricId

          $row = "" | Select Name, virtualDisk.totalWriteLatency.average,virtualDisk.totalReadLatency.average,virtualDisk.numberReadAveraged.average, virtualDisk.numberWriteAveraged.average, virtualDisk.read.average , virtualDisk.write.average

          $row.Name = $_.Name

          $row.totalWriteLatency = ($statsGrouped | where {$_.Name -eq "virtualDisk.totalWriteLatency.average"} | %{$_.Group | Measure-Object -Property Value -Average}).Average

          $row.totalReadLatency = ($statsGrouped | where {$_.Name -eq "virtualDisk.totalReadLatency.average"} | %{$_.Group | Measure-Object -Property Value -Average}).Average

          $row.numberReadAveraged = ($statsGrouped | where {$_.Name -eq "virtualDisk.numberReadAveraged.average"} | %{$_.Group | Measure-Object -Property Value -Average}).Average

          $row.numberWriteAveraged = ($statsGrouped | where {$_.Name -eq "virtualDisk.numberWriteAveraged.average"} | %{$_.Group | Measure-Object -Property Value -Average}).Average

          $row.readAvg = ($statsGrouped | where {$_.Name -eq "virtualDisk.read.average"} | %{$_.Group | Measure-Object -Property Value -Average}).Average

          $row.writeAvg = ($statsGrouped | where {$_.Name -eq "virtualDisk.write.average"} | %{$_.Group | Measure-Object -Property Value -Average}).Average

          $report += $row

     }

}

$report | Export-Csv -NoTypeInformation -UseCulture c:\xp.csv