[rawatson]

I think the author could have chosen better data for this calculation. There are a few unusual factors:

* Why use average income? Why not median family income?

* Why use median $/square foot, and then assume a 2000 square foot house? Why not just rely on median sale price?

I looked up the data for San Francisco, where median family income is $81,136 and median home sale price is $705,000.

Using the same methodology but with these income/price numbers, saving up for the down payment on a home in San Francisco takes ~14.5 years instead of 20.6. I'm not sure how this compares to other cities, but I think it's a bit more reasonable of an estimate of how long it takes to "save up for a house" in San Francisco.