Does your site contain PDF documents? Take care when reporting on the number of downloads.

One of the questions that we are asked time and time again is why are our PDF files so popular? Whilst on the surface, this would seem like a good thing, in reality it is actually a result of the Adobe Acrobat reader software. Unfortunately the bad news is that the number of downloads of PDF software by tools like WebTrends can be significantly inaccurate unless you take care to ensure that each download is only counted once.

When a visitor arrives at your site and downloads a PDF document, they will most likely be using Adobe’s Acrobat Reader software. This software downloads PDF files page by page. This often results in more than one transaction with the web server per PDF download. The longer the document the greater the number of transactions. The good news is that it is a relatively simple problem to fix. Just add a filter to exclude all requests for partial content (status code 206) or to only include transactions with the status code 200.

You will see a dramatic drop in the reported downloads, but it will be more accurate.

If you would like further information on how to solve this issue with your website statistics software, please contact us.