By default the "Recent Events" section at the bottom of any report on http://nomic.bob-space.com/agoralog.aspx will display all events that have occurred in the past 30 days. However, you can add a time variable to the URL set to an integer to display a variable length of history. For example http://nomic.bob-space.com/agoralog.aspx?contract=Insulator&time=45 will display the last 45 days of Insulator activity.
NOTE: I started logging information beginning on June 10th with Cards. Over the past month I have added substantially more tracked information, however for reports added more recently there may be significantly less history available. BobTHJ