There has been a marked increase in traffic over the last 12 months. Most notably the total number of miles travelled by van are up 6%, car miles are up almost 2% and HGV miles up 1.2%. A total of 320 billion miles were covered by the nation's vehicles, up on average by 5% on the previous year.
There is one obscure but important factor in this increase, House Sales (or lack of them). Changes to Stamp Duty have caused house sales to fall. Broadly speaking people changing jobs don't move house (in the same sort of numbers as previously); they simply commute greater distances. Whether they are tradesmen driving the van to work or an office worker dashing from home we are all travelling further, adding to the congestion on our roads.
The Government is spending £15 million on the major highway infrastructure nationally but local authorities are cutting back on expenditure. The result is that roads get busier and busier but there are no new local roads. The £21 million UTMC scheme in Ipswich has not resulted in any new road space (but should result in better traffic flow).