# Inside London's MOT-tested fleet

> Age, mileage, engine size and recorded colour among class 4 vehicles brought for an initial MOT.

- Category: Transport
- Cadence: annual
- Status: Published on a annual cadence.
- Dataset key: `mot-fleet-mileage`
- Source: [DVSA](https://open.data.dvsa.gov.uk/mot-anonymised/index.html)
- Licence: Open Government Licence v3.0 — [terms](https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/)
- Canonical page: [https://londongraph.com/g/inside-londons-mot-tested-fleet](https://londongraph.com/g/inside-londons-mot-tested-fleet)
- Machine-readable record: [https://londongraph.com/data/inside-londons-mot-tested-fleet](https://londongraph.com/data/inside-londons-mot-tested-fleet)

## Methodology

DVSA anonymised class 4 initial-test rows for vehicles kept in the eight London postal areas, grouped into broad age, lifetime-odometer and engine-size bands. Retests are excluded. Odometer readings at or below 100 miles and at or above 400,000 miles are treated as missing; vehicle ages above 60 years are excluded from the age distribution. Recorded colour is an administrative label normalized only for case and whitespace. This is the tested fleet, not every vehicle on the road: most vehicles under three years old do not yet need an MOT and are systematically absent.

## Visualisations

- [Lifetime mileage](https://londongraph.com/g/inside-londons-mot-tested-fleet): Show broad odometer bands among class 4 initial tests with a valid reading.
- [Engine size](https://londongraph.com/g/inside-londons-mot-tested-fleet?view=engine): Compare broad cylinder-capacity bands while retaining unrecorded values.
- [Recorded colour](https://londongraph.com/g/inside-londons-mot-tested-fleet?view=colour): Use a treemap for the most common administrative colour labels in each annual extract.
- [Vehicle classes](https://londongraph.com/g/inside-londons-mot-tested-fleet?view=vehicle-classes): Keep cars, motorcycles, coaches and goods-vehicle test classes separate. Caveat: This view is test activity by class; the other MOT pages remain restricted to class 4 cars and light vans.

## Citation guidance

Attribute the original publisher named above and identify LondonGraph as the visualisation and methodology layer. Do not describe live values as a historical census, and do not present placeholder values as observations.