Creating chart from powershell monitor output

My powershell monitor gives amount of seconds as output. How can I create a chart out of that? Currently the charts are about percentages even though my output from script is like this:

Write-Host "Statistic:" $output.TotalSeconds
Write-Host "Message: Copy-item duration [sec]"

I don't see any option to change this value type in the chart edit. So where should I go to achieve this?