Learners' chances of passing their theory test have dropped by a third since 2007/08 from 65.4 per cent to just 44.2 per cent in 2022/23, according to the latest DVSA figures.
Analysis of the agency's data carried out by AA Driving School also found a huge variation in pass rates by region, with the test centre where learners experience the most success seeing almost three quarters pass, while the worst sees nearly three quarters fail.
Average driving theory test pass rates were generally between 60 and 65 per cent in the late 2000s, though changes introduced a decade ago sparked a sharp fall in pass rates to around 50 per cent.
These included an increase in questions, the withdrawal of interpreters and - likely having the biggest impact - the decision to stop publishing new theory test questions online or in practice papers.
But the new analysis also shows that where you sit the theory test could also impact your chances of passing.
The test centre with the highest pass rate is in Aviemore, Scotland, where 73.5 per cent of learners are successful.
In fact, of the top ten locations with the highest theory test pass rates, all are north of the border with a combination of mainland and Scottish islands, including Barra, Harris and Mull.
In contrast, new motorists sitting their theory test in Hornsea, Yorkshire, have an average pass rate of just 23.6 per cent.
Test centres in England dominate the standings for the lowest pass rates, with Brodick on the Isle of Arran and Porthmadog in Wales the only exceptions in the bottom ten.
While fluctuations in practical test pass rates can partly be put down to routes having varying levels of difficulty due to complexity of roads, it is more difficult to explain why some test centres have far worse pass rates than others.
The analysis comes as the AA Driving School launched its own theory test app to tackle the problem, which provides learners with flashcards to make learning easier and keep them up-to-date with test pass rates.
The vast majority (90 per cent) of licence holders admitted to coming across road signs they do not understand, with a quarter (26 per cent) saying they do it very often or sometimes. Only one in ten said they never come across road signs they do not know the meaning of.
Knowledge of stopping distances was also an issue – with fewer drivers knowing the right answer the faster the car is travelling.
At 20mph (in dry conditions) more than a third of drivers (38 per cent) correctly said the stopping distance would be between 11 and 20 metres.
This fell to 31 per cent at 30mph; 28 per cent at 40mph; 24 per cent at 50mph, 24 per cent at 60mph and finally just 23 per cent at 70mph.
Alarmingly, a significant minority of drivers underestimate the stopping distance at 70mph by almost half with almost one in ten (9 per cent) saying it is less than 50 metres, when it actually takes 96 metres.
The theory test was introduced in 1996, and replaced questions about the Highway Code during the practical test.
It costs learners £23 to sit a theory test.
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