What do I say about why I left my last job? after 7 years as a janitorial supervisor

I have an interview next week and I am unsure how to explain why I left my last job as a janitorial supervisor. Thank you in advance. I do not want to blame the company. Do you mention numbers?

Practise it out loud with a friend. Mine felt natural after the third try.

Say it plainly and move on to what you can do. Interviewers usually move on if you do.