I think one could argue that earlier users of google were more likely to be programmers and that the overall proportion of "* programming" related searches has

I think one could argue that earlier users of google were more likely to be programmers and that the overall proportion of "* programming" related searches has declined, and therefore the normalisation isn't accurate. In fact this can be somewhat confirmed by checking google trends for "programming" [1] For a more accurate evaluation, the relative measure should be compared against all "* programming" searches. And if you overlay "programming" and "java programming" charts, you can see that java programming curve has declined less than the programming curve. [2] [1] http://www.google.com/trends/explore#q=programming http://www.google.com/trends/explore#q=programming [2] http://i.imgur.com/KbIm0w2.png http://i.imgur.com/KbIm0w2.png (Java - red, Programming - blue)