How do you rate movies?

I have been rating movies on IMDb for a long time now, but I have a bit of a problem with the way I do it. I would say that probably about 75% of the movies I rate, I give a 7 or an 8. If I like it, I give it an 8, and if I think it is so-so I give it a 7. In rare cases when I like it a lot I will give it a 9, and in even rarer occasions I will give it a 10. If I don’t like it very much I will give it a 6, and if I dislike it I will give it a 5 or a 4 – but that is rare; movies that bad I will probably not watch in the first place!

So effectively my range is from 6 to 9, with very few outliers. I feel like I should expand it a bit, but I have a hard time setting new parameters for myself.

How do others do it? I understand some people give it either a 1 or a 10, which is stupid and distorts the rating.