Adsense publishers should note that as of December 10th, 2007, Google will be removing top query data that is older than one year. Google is recommending that publishers save their reports prior to this date.

How to obtain top queries data from advanced reports:
If you do not already have custom reports created, select "Advanced Reports" under the "Reports" tab. Then, choose the "Adsense For Search" listing from the dropdown menu and select a date range. Select the "Top queries data" report to show and click "Diaplay Report". The system will then return the results (top queries, number of queries and percentage of total queries) which users can download as a CSV file.

Learn more about creating custom reports for Google Adsense.