Police data is anonymised to the block
The San Francisco Police Department does not publish address-level locations for incident reports. Every count in a report is expressed as “within N feet” because that is the precision the data supports. A count near an address is not a statement about that address, that building, or anyone in it.
An assessment is not a valuation
Under Proposition 13 a California assessment is the purchase price adjusted by at most about two per cent a year until the property next changes hands. A building held for decades can be assessed at a small fraction of what it would fetch. Assessed value is a tax figure and nothing more.
A complaint is not a finding
Anyone may file a complaint with the Department of Building Inspection, and it is recorded before anybody tests whether it is true. A notice of violation is different, because an inspector issued it. We count them separately and never add them together, and neither should you.
Registration is not occupancy
A business that closed without deregistering stays on the city's register. Business listings are claims on a register, not lit windows.
Rents reported are rents being paid
The Rent Board's inventory records what tenants currently pay, not what a unit would list for. In a city where most of the stock is rent controlled, a long tenancy pays far below market. It is a guide to the income a building produces, not to what a newcomer would pay.
Seams in the record
Where the city changed how it records something, a trend across that change compares two different things. The two police datasets overlap rather than abut, and 311 renamed its entire taxonomy in June 2024. We mark these next to the affected numbers rather than in a footnote.
Nothing here is scored
There is no safety grade, no risk number and no letter for the block, and there never will be. Those are opinions wearing a number's clothes. You get the records; the conclusion is yours.