Right. In terms current thinking I can't speak for an entire field, and I should say from what I have seen economics maybe still follows the lead of hard scienc

Right. In terms current thinking I can't speak for an entire field, and I should say from what I have seen economics maybe still follows the lead of hard sciences where coming up with a theoretical model and a beautiful equation on paper which is then strongly supported by empirical research is still sort of a holy grail. But today, the availability of empirical real world data or a way to go get it if not yet collected is night and day different compared to 60 years ago when many of the old economic theories were being thought up and became popular. Go read the old papers there is no data just theory. Today, economic theories and formulas can often very quickly be tested with empirical research and data. And in my opinion current economics has turned toward empirical work having weight over theoretical work How do you disaggregate? You do the best you can. And yes we do try to look at each part individually (not in a vacuum though). Because it turns out aggregating is worse. When you look at TFP the way you describe, you are not just aggregating technologies you are aggregating everything...aggregating all technologies and also whatever else is happening that K and L didn't capture. Who needs that, it doesn't tell you anything practical but that "other stuff is happening". Technology might turn out to be only <5% of TFP. There's enough evidence that TFP has too many "factors" in it to be lumped as just technology. Physicists didn't give up when they realized 95% of the universe is dark matter/dark energy that they don't understand, economics is following that lead, double down on the small stuff and hope to understand the big stuff a bit better and the best you can. I looked at your bio, not sure if you use TFP in your work or its just a personal interest. I know a bit about about market and equity research. If you have access to the data I would use PCA over TFP, if you don't have this I would just proxy a series and risk off systematic variables and focus on key known numbers. Better to ignore fake data than listen to hurtful real data. Either way we are all always guessing. https://en.wikipedia.org/wiki/Productivity_improving_technologies https://en.wikipedia.org/wiki/Productivity_improving_technol... https://en.wikipedia.org/wiki/Aggregation_problem https://en.wikipedia.org/wiki/Aggregation_problem Blah blah blah: https://www.youtube.com/watch?v=VVp8UGjECt4 https://www.youtube.com/watch?v=VVp8UGjECt4