It looks like this is a legacy trended report.
The percentage means how much that specific line item contributed to the entire pages report in that month. If there was a column for every page on your site, each row would equal 100%. However, that report only supports 5 columns.
You could try using Analysis Workspace, which is much more flexible in getting data out of Analytics.
Also PratheepArunRaj, there's a translate button available in the bottom right of each post so we can accommodate international communities