I replaced my old PC only because I went from an i5 6600 to a ryzen 7800x3d and thus needed to replace the RAM as well.
Combone that with an old 4GB 960 and an older 2TB HDD and wanting another case the math was quite easy.

It’s alao a quesrion how you interpret that? At what point is it a new PC vs upgrading? If you have replaced all parts from the original starting build?
Might explain the higher percentage