Tucker didnt follow the charts.. he was "suppose" to weigh 7.5 pounds grown, he is now 9/9.5 pounds. His parents were 4 pounds so that theory didnt work either... oh and he is solid as rock, sturdy little fella and he isnt fed alot of snacks..lol.
SO while it may work for some, it doesnt work for others...
.. you will know about the 18 month mark about what your pups adult wieght will be..