External costs and subsidies
From Mark Delucchi, ACCESS NUMBER 16 • SPRING 2000, page 12:

External costs and subsidies for different passenger- transport modes (cents per vehicle mile, except last row is cents per passenger mile)
[Numbers in brackets are my best estimates]
COST ITEM GASOLINE AUTO ELECTRIC AUTO

TRANSIT BUS

LIGHT RAIL HEAVY RAIL
Air pollution 0.8 to 13 [2.0] 1.5 5.4 to 123 [20.0] 5* 5*
Oil use, water pollution 0.3 to 1.5 [0.8] 0 . 4 1.5 to 8.7 [4.0] r r
Noise 0.01 to 2.0 [0.2] 0.1 5 0.5 to 10.0 [2.0] r r
Congestion 4.0 4 . 0 8.0 not estimated not estimated
Accidents 2.5 2 . 6 3 .5 2 * 2*
Marginal highway and service costs 0 . 1 0 . 1 1 . 5 0 0
Unpriced parking 0 to 8 [0] 0 to 8 [0] 0 0 0
In efficient highway user taxes and fees,
meant to cover highway costs
- 2 . 7 0 0 (exempt from fuel taxes) 0 0
Government subsidy:
Operating costs minus fares

Operating + rolling-stock costs minus fare
Total operating + capital costs minus fare * *
0
0
0
0
0
0
33 9
[ 39 8 ]
4 6 5
685
1 , 13 7
2 , 8 0 0
372
797
1 , 177
Extra private costs relative to gas auto 0 0 to 16 [8] see subsidy see subsidy see subsidy
Total cents per vehicle-mile 5 to 28.4 [6.9] 8.8 to 24.8 [16.8] 359 to 620 [437] 694 to 2,809 381 to 1,186
Passengers per vehicle assume 1.0 assume 1.0 10.9 (avg.) 25.7 (avg.) 22.3 (avg.)
Total cents per passenger- m i l e --------> 5 to 28.4 [6.9] 8.8 to 24.8 [16.8] 33 to 57 [40] 27 to 109 17 to 53

* Data are not available for these numbers, which are estimated based on my studied judgment.
* * Note that, because the official statistics do not report passenger fare payments by individual transit mode, it is not possible to calculate the actual government subsidy for each mode. I have assumed that ratio of fare payments to operating expenses is the same for all modes.

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