I'm putting together a graph to compare the different ratios of PG/VG in e-liquid to try to get a better understanding in terms of which direction the market is shifting. As of yet, I've been unable to find anything with specific studies/surveys catered to my needs and anything I have found would basically result in pure conjecture on my part.
If anyone has any good insight or knows of any good articles online that might aid me in my task, it would be much appreciated.

If anyone has any good insight or knows of any good articles online that might aid me in my task, it would be much appreciated.