People expect resumes to display quantifiable impact. What if the impact at your company was not measured in quantitative ways?

You know what you worked on empowered users, improved efficiency, reduced operational cost, but by what percentage? Do you add an estimate? If yes, how? If no, is there any ways to make it work?

I don't want to lie on my resume/make up numbers that are not measured so I didn't include any. But there seems to be no win without quantifiable results.

Any advice?