New statistics show that during 2017, 86% of cars exceeded the speed limit on roads with a 20mph limit – with 18% breaking the limit by more than 10mph.
The DfT statistics, published on 27 September, measure speed and compliance at sites where the road conditions are ‘free flowing’ – for example roads with no junctions, hills, sharp bends, speed enforcement cameras or other traffic calming measures.
The figures show the percentage of cars exceeding 20mph limits rose year-on-year by 5% in 2017 – with the percentage of those breaking the limit by more than 10mph rising by 3%.
However, the DfT acknowledges that free flowing conditions are not typical of most 20mph roads.
Single carriageway roads where the national speed limit applies (60 mph) had the highest levels of compliance, with only 9% of cars exceeding the limit.
However, this figure represents a 1% rise on 2016 when only 8% exceeded the speed limit.
On motorways, 48% of cars exceeded the 70mph speed limit, with 12% exceeding it by more than 10mph. Again, these figures show a year-on-year rise; compared to 46% and 11% respectively in 2016.
On 30mph roads, 52% of cars exceeded the speed limit with 6% exceeding it by 10mph or more – 1% fewer than in 2016.