The OWL + USB software displays bar charts of data as a default.
The Initial screen will show the blocks of data covering the years over which data has been stored.
If you double click into a green block you will see the data for the months of that year for which data has been stored
If you double click into one of the months you will see the days
Double clicking into the days will show you the hours
Double clicking into the hours will show you the minutes.
To back out of the fine detail charts select the period you want to back out to in the data period list on the top right of the chart.