Article is talking about new construction, not overall unit size.

1 - Seattle - 661 square feet.
2 - Portland - 685
3 - Queens - 692
4 - Brooklyn - 712
5 - Detroit - 726
6 - Manhattan - 737
7 - Washington D.C. - 744
8 - San Francisco - 756
9 - Philadelphia - 764
10 - Silver Spring, MD - 770

I’m not sure, but I’m pretty sure I have more than 685 square feet of just bookshelves…