How to get the sales volume of the entire category?

Hi,

Let say if the sales of my garlic press have gone down significantly in the last 3 days, is it possible to view the sales volume of the entire garlic press category? I am trying to figure out whether the problem is my listing or it’s a trend that affects the entire garlic press category. Is there a place/tool that I use to view this info? Please advise. Thanks.