It has been estimated in Britain that the amount cars pay in licence fees, sales and fuel taxes covers the cost of road infrastructure, collisions, congestion and ambient environmental impacts. (note 1). Even accepting this dubious assertion, it underrates cars' cost by discounting the capital value and opportunity cost of all the land under road and car parks. This is a larger area for the car system than for any other transport configuration so the difference should be accounted as a car culture cost. In the first world it's highly developed, valuable, well infrastructured landspace, worth billions of dollars in annual lease value in any fair sized city. This is the reason cars don't pay for themselves.
The following algorithm estimates the cost of cars' landspace use in Australia over and above the landspace of an optimised urban transport system. Some data were available but a number of assumptions were still necessary, these are identified in the following table.
| Road Rent Costings | ||||||
|---|---|---|---|---|---|---|
| Category | No | Name | value | unit | Notes | |
| Statistics | 1 | Urban Arterial Road Length | 12,441,000 | m | note 2 | |
| 2 | Urban Local Road Length | 84,834,000 | m | note 3 | ||
| 3 | Area of car parking space | 23.4 | m2 | note 4 | ||
| 4 | Total Tax on cars | $ 14,000,000,000.00 | $A | note 5 | ||
| 5 | Aust GDP | $620,963,000,000.00 | $A | note 6 | ||
| Assumptions / estimates | 6 | Arterial Road Width | 16 | m | note 7 | |
| 7 | Local Road Width | 9 | m | note 8 | ||
| 8 | Ratio of cross subsidized parking spaces to cars | 2.5 | spaces | note 9 | ||
| 9 | Urban car fleet | 7,695,098 | cars | note 10 | ||
| 10 | Rent per m2 pa | $ 50.04 | $A | note 11 | ||
| Assertion | 11 | optimal urban road carriageway width | 6 | m | note 12 | |
| Calculations | 12 | Arterial Urban Road Area | 199,056,000 | m2 | note 13 | |
| 13 | Local Urban Road Area | 763,506,000 | m2 | note 14 | ||
| 14 | Total Urban Road Area | 962,562,000 | m2 | note 15 | ||
| 15 | Optimal Urban Road Area | 583,650,000 | m2 | note 16 | ||
| 16 | cross subsidized road area | 378,912,000 | m2 | note 17 | ||
| 17 | cross subsidized car park area | 450,163,247 | m2 | note 18 | ||
| 18 | car culture appropriation | 829,075,247 | m2 | note 19 | ||
| 19 | space appropriation per car | 107.7 | m2 | note 20 | ||
| 20 | Annual rent due (annual space subsidy of car culture) | $ 41,489,291,744.20 | $A | note 21 | ||
| 21 | Space subsidy as proportion of GDP | 7 | % | note 22 | ||
| 23 | Total car taxes as a proportion of space subsidy | 34 | % | note 23 | ||
| 24 | Annual rent due per urban car | $ 5,391.65 | $A | note 24 | ||
| 25 | Annual cross subsidy per person | $ 2,183.65 | $A | note 25 | ||
| 26 | Annual unpaid rent from urban car drivers | $ 3,208.01 | $A | note 26 | ||
This setup concludes each urban car user should be paying an annual lease value of some thousands of dollars in extra space appropriation costs. Those with better access to figures or who dispute values or assumptions might plug them into the algorithm for results they'd credit; I defy them to find the amount insubstantial. You may download the zipped spreadsheet by clicking here (MS Excel 97 format).
This is a profound and serious inequity, the extra space afforded drivers costs time, money and efforts of non car-users, from a trade off they neither chose nor benefit from. If a tax, calculated via an algorithm like the above, were imposed it would have the beauty of increasing the tax on remaining car users as others gave up the practice, with relief from rising tax only arising from reductions in road and car park area; but a ban would be more equitable.
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