This is the page where you can get rid of old or otherwise unwanted statistics that are just taking up space. It's easy... a bit too easy, perhaps. So be careful.
Just click on the checkbox next to each interface that you want the time restrictions, which you set at the bottom of the form, to apply to. You can also, if you don't use Netscape 4.x on Linux, use the "Toggle" button to, you guessed it, toggle every checkbox (the On ones will turn Off, and vice-versa). Be careful with that, now. Then enter the From and To times between which you want to delete the collected stats on each interface you selected above.
If you delete *all* the stats for a particular interface, keep in mind that it will still be configured for monitoring and collection will continue on it as usual. You have to remove it in the SNMP or Localhost Interfaces configuration section for collection on it to stop.