If you use my Get-TaskPlus function from Task Data Mining – An improved Get-Task you can do something like this
Get-TaskPlus -Start (Get-Date).AddDays(-1) -Details -Realtime |
ForEach-Object -Process {
$_ |
Add-Member -MemberType 'NoteProperty' -Name 'Execution Time' -Value ("{0} ms" -f [math]::Round((New-TimeSpan -Start $_.'Task Started' -End $_.'Task Ended').TotalMilliseconds, 0)) -PassThru
} | Export-Csv -Path .\ExportTasks.csv -NoTypeInformation -UseCulture