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More cars, but less motoring

6 Jun

There has been quite a lot of interest  in the idea of ‘peak car‘ recently which proposes that we may have already reached a point of ‘peak car’ and that from here on car use may decline rather than grow further or level off. Total vehicle mileage in the UK has indeed declined since 2005 and in London since the early 1990s. Read about this in The Independent and in the New Statesman. Significantly, the government predicted back in 2003 that traffic would grow by 25% by 2025 and that vehicle ownership would grow by 30%. Both of which now seem very unrealistic and should probably be reviewed!

By contrast the number of cars on UK roads has continued its relentless rise  (growing 27% during Labour’s term in office from 1997-2010). This should mean that each cars are each traveling less distance per year and this is indeed true. Mileage per car peaked at 10,600 in 1995, and is now down to 9,200 and heading down to levels last seen in the 1960s!

Mileage per car per year

Interestingly the percentage of 21-29 year olds with driving licenses has also fallen. It is now 65%, down from a peak of 74% in 1992-1994 and a percentage which was last seen back in 1985.

Chart sources:
Vehicle mileage: ‘TRA9908 Road traffic by type of vehicle, historic in kilometres
Vehicle stock: Various sources from Vehicle licensing statistics

‘Costs’ and ‘benefits’ of 80 mph speed limits

2 Mar

The government is wanting to increase motorway speeds from 70mph (112km/h) to 80 mph (130 km/h). The Transport Secretary explains: “We need to do this on a pretty rigorous cost-benefit analysis basis…at the moment there are a clear set of criteria for making these decisions. Perhaps we ought to ask if we are using the right set of criteria”.

Netherlands is also planing to increase it’s motorway speed limit to 130 km/h while Spain is currently lowering its speed limit from 120 km/h to 11o km/h to reduce fuel imports! Check out this useful blog post on the subject confusion that we are in at present.

Lets do a rough and ready cost-benefit analysis given that both the ‘costs’ (ie mainly injuries, deaths) and the benefits (mainly a few minutes off journey time for car drivers) can be reasonably easily calculated so lets have a go.

For every 100 miles driven one will save 10 minutes in travel time (75 mins, down from 85 mins). This does of course depend on having a clear road and no holdups due to crashes.

Lets look at the ‘costs’. According to a review of changes to speed limits conducted for the authorities in British Columbian 2003 the rate of crashes and fatalities is likely to increase significantly. They don’t report on any countries increasing speed from 70 mph to 80 mph (110km/h to 130km/h). They do however report on when Switzerland reduced its speed from 130km/h to 120km/h with reduced fatalities by 12% and when Sweden reduced speeds from 110km/h to 90km/h and fatalities declined by 21%. Also interestingly when the UK reduced speeds from 100km/h to 80km/h  and saw a reduction of 14%.

By contrast when Australia increased its speed limit from 100 km/h to 110 km/h it saw an increase in fatalities of 25%. Increasing speeds in the USA from 89km/h to 105 km/h often had associated increases in fatalities of about 20%.

The Wikipedia Road Safety Article has a useful table which shows motorway casualty rates in the first column and speed limits in the right column (this is not properly referenced though). Is it just me or is it significant that all the worst countries have high speed limits and all the most safe countries have low ones?

Speed safety stats

Do also check the excellent UK Speed Limit article which has a lot of detail of the history of UK speed limits and which is fully referenced.

So, lets get back to an estimate of the ‘costs’. In 2008 there were 158 fatalities on Motorways. As a rough indicator based on the above research, it looks like we can expect about 30 more fatalities. There are many other costs not yet considered including: increased fuel usage, more road noise, more carbon emissions, more stress, more delays caused by crashes. These concerns are echoed by the AA Trust who warned back in 2005 against a blanket increase in the motorway speed limit to 80mph saying that in the absence of strict enforcement to would lead to “unacceptable enforcement drift to 90 mph” – which would “increase the risk of accidents and raise the total of fatal and serious injuries”.

Incidentally, almost half of UK drivers wanted vehicles to be fitted with Speed Limiters which are already used on trunks which are limited to 56 mph and on express coaches at 65 mph which will also be using the motorways.

There there is the research study conducted by the Institute of Advanced Motorists and the RAC Foundation back in 2006 found that some 26% of motorway drivers were following the vehicle in front too closely and that on the M4 the figure was 50%. Do we really want people tailgating at 90 mph?

The ‘cost’ is some 30 deaths and more crashes, which, errr.. might actually reduce the benefit by creating more hold-ups. Also, increased road noise, fuel consumption and driver stress. The benefit is some 10 minutes off journey times per 100 miles (assuming that there are no congestion, road works or crashes to contend with).

At this point transport consultants would convert these costs and benefits into money using standard calculations used by transport planners. I won’t do this because I don’t have the figures to hand and I find the idea rather offensive.

Finally, here is a chart showing road deaths on UK roads since 1929. Be aware that it was a nasty Labour government that introduced the 70mph speed limit in the 1960s after some terrible crashes in fog. since then fatalities have reduced impressively over the past 40 years under both Labour and Conservative governments. Is this trend going to continue going down or are all these ‘motoring’ biased initiatives (such as removing school crossing patrols, re-timing lights in favour of motorists, increasing speed limits, cutting back on bus services, bus lanes and cycle lanes), are we going to see the graph turn up again. I do do hope that this in not going to be the case.

Killed on British Roads

What I would like to is see now is someone doing a FOI request on the Department for Transport requesting their official report on the subject. There is the nice WhatDoTheyKnow website that makes this very easy to do.

How many people do drive their kids to school?

10 Jan

The government has just published a set of indicators indicating how children got to school across the country last year broken down into primary and secondary age groups. A graph based on the percentage of children walking, cycling or taking public transport to primary and secondary schools organised with the authority with the lowest rate on the left and the highest on the right comes out like this. The red line if for primary age children and the brown line for secondary.

Getting to school 2009-2010 by Authority

It shows that even in the authorities with the lowest rates for primary schools there are nearly 50% of children walking/cycling etc and that in the highest it is up to about 90%. The average across the country is about 63% for primary and 70% for secondary.

The papers claimed that the statistics showed that the schools with the highest driving rates were the rich and rural ones and the ones with the lowest were urban and not so rich. It isn’t actually that clear – here are the only ones where more than 50% of children are being driven: Herefordshire, Windsor and Maidenhead, Solihull, Cornwall, Surrey, St. Helens and Sefton.

The London borough feature prominently in the list of places with the lowest driving rate with Portsmouth being the most interesting inclusion – Portsmouth also has been pioneering area-wide 20mph speed limits with very encouraging results. Here are the ones with over 80% walking etc starting with the highest: City of London, Islington, Camden, Westminster, Isles of Scilly, Newham, Hammersmith and Fulham, Tower Hamlets, Southwark, Lambeth, Kensington and Chelsea, Hackney, Portsmouth.

The slight anomalies for the rates for secondary schools to the right of the graph are probably data errors. The blip down to 40% is for Brighton and Hove and the one to 50% is for Ealing.

My conclusion is that it is a minority of parent who are causing all this trouble and one should bear in mind that many of the ones who do drive will park their vehicles some way from the school gates and walk the final section. I suspect that there is a lot of self selection of drivers going on which results and that ‘die hard drivers’ and ‘complacent car addicts’ are well represented outside the school gates.

Are we winning?

15 Dec

In one way everything seems to be getting worse. A huge problem and one that is getting worse as the number of vehicles increases. However…. there are also some interesting positive signs. Here are a few of them.

We now have a prime minister and a mayor of London who are keen cyclists. William Ford (Henry Ford’s grandson) who is executive chairman of the Ford Motor company recently said “The day will come when the notion of car ownership becomes antiquated. If you live in a city, you don’t need to own a car”. I think it is interesting when someone in that position says that. Simon Kuper commented in the Financial Times “Cars are going out of fashion.. Once cars lose speed and power, they become unglamorous everyday tools, like washing machines, and nobody, presumably, derives status from their washing machine”. Thanks to ‘Life outside the box‘ for bringing my attention to that one.

Here is some evidence:

This is a video I put together of people and traffic crossing London Bridge (not Waterloo Bridge as I call it in the video). Notice that there are virtually no private cars and that the vast majority of people are on foot.

Then there here is one I make of a a street in centre of my home town of Ipswich. For sure most of the space is again allocated to car drivers but most of the people are on foot.

In relation to that comment, here is a video I took during a recent trip to Detroit showing a virtually completely empty freeway outside their world headquarters near Detroit. Detroit is a great place to cycle btw and they spending a lot of money making it better.

Finally, a couple of images from my company showing the decline in vehicles in London in the past 10 years and the increasing numbers of bicycles.

Declining numbers of cars in London shown as red

Increasing use of bicycles in London shown as blue

Major motorcar manufacturers have needed to be bailed out and the British Motorshow has been canceled again (both the 2010 and 2012 shows have now been cancelled) and may in reality never return.

All this is not a reason not to keep pushing for change, it is just a reason not to give up!

Welcome to another 52,000 vehicles!

29 Nov

By the end of 2009 there were 52,000 more vehicles on GB roads than at the end of 2008 and this is despite a big down-turn in car sales, and government money in a scrappage scheme to encourage sales until the end of March 2010. The scrappage scheme did at least take one old car of the road for each qualifying new car.

Between 1997 and the end of 2009 (roughly the period Labour’s term of office) the number of cars on GB roads increased by over 7 million or 27%! Clearly the purchasers of these additional vehicles plan to leave them somewhere when they are not in use. This may be outside some new house on a shiny new driveway or somewhere else out of the way however I am sure many front gardens were dug up with associated dropped kerbs, creating their own problems for pedestrians. Many will of course have been squeezed onto the highway where-ever possible, across pavements, on verges etc etc. Here is a graph showing the relentless increase in vehicle numbers in Great Britain since 1950.

GB vehicle stock 1950-2009

And here is the graph showing just the registrations and scrappages each year for 1960 onwards. The bumps and lumps in the curve generally fit with the state of the economy.

GB vehicle registrations and scrappages

The lack of sales and relatively low increase in the vehicle stock is in general treated as a problem by government because of the lack of ‘growth’ which is in their view always a good thing. In human beings uncontrolled growth is known to a huge problem (we call it cancer!) and if the pet hamster we had as a kid hadn’t stopped growing at the right moment then results would have been disastrous as pointing out in this wonderful little animation.

There are however also encouraging signs that we may be approaching a peak in vehicle numbers and that they could drop significantly in the coming years. Car clubs are growing fast, cycling is growing fast, rail travel is growing fast and mileage in cars per head of population has actually been on its way down for some time now. In addition the iPhone, blackberry and other smart phones can only be used when someone else is driving. Personally I think it is the mobile communications devices that will encourage most people out of their cars so that they can work while traveling. That is the subject for one of more later post though!