2017 version of model is 3x the size as 2021 version

SketchUp Pro
1

I work in SketchUp Pro version 21.1.332 64-bit.

When I save a 2017 version of a file, the 2017 version is 3 times the size. Nothing else about the files is different. What’s that all about?

2

2021 has a new compression algorithm.

3

Sweet. Thanks!