Does your number of sexual partners matter?

Just a question but do you guys feel that the number of sexual partners your significant other has had in the past is important? What about if you just started dating someone? It was brought to my attention that the number of hook ups I've had is kind of a negative thing. I've only had 3 serious boyfriends before and a couple of girls I casually dated in high school. In between though when I wasn't dating anyone I would hook up with guys a couple times a month, overall I guess the number has gotten quite big and I never payed too much thought to it. Now I feel kind of ashamed because I can't really put an exact number on it. Any input is appreciated.