If you want to track how many times your Files have been downloaded from the Help Center, you can build a custom report to generate this information. Go to Reports > Stats > Create Statistic. Enter a title for your report and the following query:
SELECT downloads.id, downloads.date_created, downloads.title, downloads.num_downloads
FROM downloads
ORDER BY downloads.num_downloads
You can also add downloads.num_ratings to the SELECT line if you want to see the number of ratings per File too.