What do the % mean on your power profile?

What do the %’s relate to when you hover over the power bar graph on your profile?
Thanks

They did a good write up on ZwiftInsider.com about this as it happens - Rider Categorization Based on FTP: How Do I Rank? | Zwift Insider

Under the “method 2” section on that page:
Mouse over the … bars to see a percentile ranking against a sampling of “serious cyclists”… The percentile grade is split by gender.