Only relatively small project can afford a rewrite. So, this is statistic among projects that can affod a swith. And as far as I can see, this is eigenvector of

Only relatively small project can afford a rewrite. So, this is statistic among projects that can affod a swith. And as far as I can see, this is eigenvector of trend. First derivative of actual state of things. More informative of the state of fashion today