Age

The city's licence file carries a start date. Inside the district the median business has held the same licence for 24.7 years; 104 of 153 are past twenty, 34 are past forty, and 7 started in the last five.

0102030405060years holding the same licence
One dot per licensed business inside the district, stacked by five-year band of how long the licence has run.

Inside the line, and just outside it

The same measure for the 46 licensed businesses within a hundred and fifty metres of the boundary and outside it: a median of 18.7 years, 21 past twenty, 2 past forty.

insideoutside, within 150 mmedian years24.718.7past twenty, %6846past forty, %224under five, %515
Inside the historical district (153 licences) against licensed businesses within 150 m of it and outside (46); the three shares are percentages of each group.

Both columns count active licences only. A business that closed leaves the file, so neither column is a survival rate — it is the age of what is standing.

When they started

31960s71970s341980s251990s512000s232010s102020s
Licences still active, by the decade they started.
11965111197331119781341981416198451219875321990544199632519993372002616200510542008622201142120142112017533202122120242
Licences still active, by the year they started. The shape is the product of two things at once — how many opened, and how many of those are still trading.

The oldest sixteen