Change Auditor is not able to report on how long it has been since a user has logged on. CA will tell you when an event occurred, such as a logon event, but it cannot tell you how long it has been between those events.
We have another product, Enterprise Reporter, which is able to provide these types of reports. For example, ER has the following canned reports:
Users Not Logged On In The Past 30 Days
Users That Have Never Logged On
Locked Accounts
ER has a vast amount of reports for AD objects, NTFS reports and reports about Computer specific information. If you would like more information about ER, please see the following page or ask your Sales Rep:
https://www.quest.com/products/enterprise-reporter/