The cost benefit with on 20mph seems to miss a couple of large factors:
– STATS19 data show a long term accident rate fall of just under 2.5% pa. This would swamp the estimated reductions used
– there is no account taken off the lost time from slower journeys. Using average journey length and how many taken with a modest increase in journey times shows that the accident reduction rate would need to be well over 100% to exceed the increased costs
It is important to have a discussion about the numbers and the assumptions that lead to them.a suitable forum would support the democratic process
The cost benefit with on 20mph seems to miss a couple of large factors:
– STATS19 data show a long term accident rate fall of just under 2.5% pa. This would swamp the estimated reductions used
– there is no account taken off the lost time from slower journeys. Using average journey length and how many taken with a modest increase in journey times shows that the accident reduction rate would need to be well over 100% to exceed the increased costs
It is important to have a discussion about the numbers and the assumptions that lead to them.a suitable forum would support the democratic process