This PDF lists figures for Seattle's Class A and B office space on the bottom of page 2: http://team.transwestern.net/Market-Research/Documents/West%20-%20Seatt

This PDF lists figures for Seattle's Class A and B office space on the bottom of page 2: http://team.transwestern.net/Market-Research/Documents/West%20-%20Seattle%20Office%20Outlook%20-%20Q1%202017.pdf http://team.transwestern.net/Market-Research/Documents/West%... According to this, Seattle has 50.7 million square feet of Class A office space. Amazon's 8.1 million square feet is 16%. There are 53 million square feet of Class B office space.