And if we break it down each Census Tracts price per square foot, we see a similar pattern.

Again, while being skewed by the availability of data, aggregating the apartment listing to census tracts shows a different pattern than individual apartment listings. Here, the data show that the most expensive census tracts are actually in Marin County or in the South Peninsula around Silicon Valley. This data should be normalized to prevent larger area census tracts from dominating the visualization.