How do you change facebook work history to indicate a job promotion?

[Jenn]

I was recently promoted at work. I keep my facebook very updated and I would like to show in my work history that I have been promoted. I can't figure out how to show that I was promoted. I can delete my past position and in place of that put my new position, but I don't want to do it that way. Any Suggestions?
I know how to edit my page. I don't know how to show a promotion. That help page has no information on job promotions.

[Ash]

Use this link
https://www.facebook.com/help/334656726616576/