My rating is not included in imdb movie ratings

I tried rating several movies, including ones that have very little ratings, and although my rating is saved whenever i come again on rating page for each movie, the overall ratings have not increased. For example if movie had 10 ratings, and I rate it, there is still 10 ratings. Am I doing something wrong? I only tried this for about 10 movies, meaning did not overdo anything or break any rule. I have not more accounts but one, although i share same ip address as 10000 people, could it be cause?

I tried viewing overall number of ratings from logged out browser, or different browser, or browser in incognito, or from different pc and ip address, and really movie's number of ratings have not increased!