In short
The percentage of practical-test candidates who pass at a given test centre or nationally.
The pass rate is the percentage of candidates who pass their practical driving test, either nationally or at a specific test centre. The UK national average is around 48%; individual centres range from about 30% to over 70%.
Pass rates vary mostly because of the local road environment (a busy urban centre is harder than a quiet rural one), not examiner leniency.
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