Debunking the Data Behind Seattle's 'Explosion of Demolitions'

A post by Ethan Phelps-Godman critiques recent claims by multiple publications about an "enormous and unprecedented increase in demolitions." The problem, according to Phelps-Goodman: it "simply isn't true."

"The erroneous analysis started in Schema Design's ARCADE magazine, which ran a story and accompanying graphics showing the number of demolition permits per year growing from a mere 14 in 2005 to an expected 875 in 2015. Knute Berger followed up with a column in Seattle Magazine that cited the ARCADE piece and a supposed 8-fold increase in demolitions. In reality, demolitions are down from their previous peak in 2007 and 2008 and roughly in line with long-term trends."

The error arises from bad data in a dataset titled 'Building Permits issued in the past five years,' which has since been corrected. According to Phelps-Goodman, the data only looks "plausible if you're already inclined to believe the article's conclusions."

Better data, according to Phelps-Goodman, is found with the Department of Planning and Development, which shows demolitions up for 2014 from the 20-year average and declining in 2015—far from the eight-fold increase claimed in Seattle Magazine.

Phelps-Goodman acknowledges that the definition of "a lot" can vary—so the current levels of demolitions might still seem some high to many people. But better data and the correct historic comparison can offer a more accurate perspective on current trends.