Rent control is not read
The District does regulate rents: they are controlled under the Rental Housing Act and buildings are registered with the Rental Accommodations Division. That register is not published as data we can read, so this report does not tell you whether a unit is covered, and never implies it. Do not read the absence of a rent-control line as evidence a building is exempt. The Rental Accommodations Division is the authority on that question.
The offence location is a block, not an address
The Metropolitan Police publish the hundred-block rather than the address. That is the District's own choice about how precisely to locate a crime, and it means an area count is accurate to a block rather than to a building. The feed carries no demographic column at all, which is unusual and welcome.
A 311 request is not a finding
A service request is what somebody reported. The District records it before anyone has been to look, so a count of vacant-property reports is a count of reports, not of vacant properties.
What we choose not to read
The permit feed publishes the owner's name and the applicant's. The certificate-of-occupancy feed publishes the property owner, the owner's address and who permission was granted to. None of those columns are read here, in any section, and none will be. This product describes a place, never a person.
A year that did not answer
Because each feed is split by year, a slow portal can lose one year of a ten-year window. Where that happens the report names the years it could not read, so a low count is explicable rather than mysterious.
The city line
Coverage stops at the District boundary. Arlington, Alexandria, Prince George's County and Montgomery County are different jurisdictions with their own records, and nothing here covers them.