Weird ?, but about what % of female muslims cover at least their hair?

I can't help but notice that there are a lot of them who don't. (I'm one of them, but I want to and don't mind; difference is I live with parents who don't like Islam and I would probably get kicked out if they found it. But, at least I want to!) And as per the people I see, these are, for the most part, women born and raised a muslim. I'm just curious statistic wise.