I have a problem with the Performance Metric Widget in a custom dashboard. I'm monitoring a custom monitor fetching numeric values through a script. The widget can show a graph when "Show polled data" is selected but if I for example select "Last 30 days" nothing is shown, it say "Data not available for the given values". If I view the monitor itself I can see history report like normal, and select both "Last 7 days" and  "Last 30 days" and problably all the rest as well.

So how can I make the widget to show last 30 days?