It is very important to keep our dog at an adequate weight. Unless your vet advises otherwise, you should try and keep your dog in the weight-range typical for his or her breed and gender.
Here we present a chart of the weight distribution for Yorkshire Terrier dogs. The weight of a typical female ranges from 2.8kg to 4.3kg and that of a male from 3.1Kg to 4.6kg. That is, 6.2lbs to 9.5lbs for females and 6.8lbs to 10.1lbs for males.