$results = Get-Counter "\Network Interface(Microsoft Hyper-V Network Adapter)\*" -SampleInterval 1 -MaxSamples 60
#インスタンス名は  (Get-Counter -ListSet "Network Interface").PathsWithInstances を実行して確認してください。例、 "\Network Interface(Microsoft Hyper-V Network Adapter)\*"

$csamples = $results.CounterSamples

$grouped = $csamples | Group-Object Path

$avgbps = ($grouped | Where-Object {$_.Name -match "Bytes Total/sec"} | ForEach-Object {$_.Group.CookedValue} | Measure-Object -Average).Average
$maxsent = ($grouped | Where-Object {$_.Name -match "Bytes Sent/sec"} | ForEach-Object {$_.Group.CookedValue} | Measure-Object -Maximum).Maximum
$maxrcvd = ($grouped | Where-Object {$_.Name -match "Bytes Received/sec"} | ForEach-Object {$_.Group.CookedValue} | Measure-Object -Maximum).Maximum
$maxbps = [Math]::max($maxsent,$maxrcvd)
$outerr = ($grouped | Where-Object {$_.Name -match "Packets Outbound Errors"} | ForEach-Object {$_.Group.CookedValue} | Measure-Object -Maximum).Maximum
$recerr = ($grouped | Where-Object {$_.Name -match "Packets Received Errors"} | ForEach-Object {$_.Group.CookedValue} | Measure-Object -Maximum).Maximum
$bwidth = ($grouped | Where-Object {$_.Name -match "Current Bandwidth"} | ForEach-Object {$_.Group.CookedValue} | Measure-Object -Average).Average
$maxqlen = ($grouped | Where-Object {$_.Name -match "Output Queue Length"} | ForEach-Object {$_.Group.CookedValue} | Measure-Object -Maximum).Maximum

$outstr = "Avg. Throughput : {0:N2} Mbps ({1:N2} MB/s)" -f ($avgbps * 8 / 1000000),($avgbps / 1000000)
$outstr += "`nAvg. Bandwidth Use($($bwidth /1000000)M) : {0:N2} %" -f ($maxbps * 8 / $bwidth * 100)
$outstr += "`nMax. Output Queue Length : {0:N0}" -f $maxqlen
$outstr += "`nMax. Packets Outbound Errors : {0:N0}" -f $outerr
$outstr += "`nMax. Packets Recieved Errors : {0:N0}" -f $recerr
$outstr