Lifetime of Older Delphi Versions

Did you ever wonder how long it takes that most of the users of an older Delphi version switch to the newer one?

Well, this question could be answered simply by looking at the sales figures of Embarcadero; however I doubt that Embarcadero will make the sales figures available to the public. An idea to get some insight to this question would be to exploit the search statistics of Google. These numbers are publicly available (at least the relative numbers) and certainly provide an indication of how many people are (still) working with a particular version of Delphi.

Here are the results of this approach (the data points are weekly averages scaled to a maximum of 100%):

So what I did, was to visit Google Trends, enter the following keywords, and download the data provided by Google. Search keywords: "Delphi 2009", "Delphi 2010", "Delphi XE", "Delphi XE2", and "Delphi XE3".

The results clearly show that the decay of a particular search keyword immediately starts after the launch of a new release. The interest in the old release drops within a few months to half of the initial interest. Only Delphi 2010 needed almost a year to drop to 50% - which may be an indication that the move to XE was judged excessively cautious by the users.