Table B-20 Estimated Measures of Reliability for Shipment Characteristics by Commodity Group and Mode of Transportation for State of Origin: 2002 and 1997
Friday, May 24, 2013
Table B-20 - Estimated Measures of Reliability for Shipment Characteristics by Commodity Group and Mode of Transportation for State of Origin: 2002 and 1997
[Estimates are based on data from the Commodity Flow Survey. Because of rounding, estimates may not be additive]
All Commodities
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 6.0 | 5.1 | 10.1 | 9.6 | 10.6 | 14.8 | 15.8 | 6.4 | 23.4 | 14.8 | 5.0 | 19.6 |
| Single modes | 7.4 | 5.9 | 12.1 | 10.3 | 11.3 | 15.6 | 15.9 | 6.8 | 24.7 | 10.9 | 8.4 | 15.0 |
| Truck | 7.6 | 6.5 | 12.8 | 11.1 | 15.3 | 18.2 | 13.5 | 5.5 | 18.9 | 13.5 | 9.3 | 16.7 |
| Rail | 22.5 | 12.8 | 40.3 | 22.6 | 10.6 | 36.9 | 25.3 | 15.2 | 49.3 | 14.3 | 8.5 | 15.6 |
| Water | S | 32.1 | S | S | 28.5 | S | S | 33.7 | S | S | 30.6 | S |
| Air (including truck and air) | 38.0 | 22.1 | 27.7 | S | 30.1 | S | S | 39.6 | S | 6.9 | 6.6 | 13.9 |
| Pipeline | S | 45.9 | S | S | S | S | S | S | S | S | S | S |
| Multiple modes | 16.3 | 10.5 | 29.1 | 48.8 | S | S | 27.8 | 25.2 | 20.8 | 9.9 | 7.6 | 15.6 |
| Parcel, USPS or courier | 16.8 | 12.1 | 32.9 | 16.8 | 12.9 | 23.9 | 16.6 | 13.0 | 23.8 | 9.9 | 7.6 | 15.6 |
| Truck and rail | 24.3 | 27.2 | 12.2 | 24.2 | S | S | 24.3 | 32.6 | 8.7 | 26.1 | 19.3 | 32.9 |
| Other multiple modes | S | S | S | S | S | S | S | 46.7 | S | 28.9 | 40.0 | 73.0 |
| Other and unknown modes | 20.3 | 17.5 | 26.9 | 28.0 | 27.0 | 57.0 | 18.8 | 24.0 | 6.8 | S | 22.2 | S |
SCTG 01-05, Agriculture products and fish
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 20.6 | 10.8 | 22.5 | 39.6 | 22.8 | 43.1 | 42.3 | 16.4 | 92.9 | S | 24.5 | S |
| Single modes | 20.6 | 11.0 | 22.5 | 39.1 | 22.7 | 41.6 | 42.2 | 16.7 | 97.0 | S | 19.5 | S |
| Truck | 20.2 | 10.5 | 21.8 | 43.2 | 16.9 | 38.9 | 35.4 | 17.7 | 49.5 | S | 19.9 | S |
| Rail | S | 34.7 | S | S | 34.2 | S | S | 45.9 | S | 27.3 | 23.6 | 67.6 |
| Water | S | S | S | S | S | S | S | S | S | 31.6 | 31.6 | S |
| Air (including truck and air) | – | S | S | – | S | S | – | S | S | – | 33.0 | – |
| Pipeline | – | – | – | – | – | – | S | S | S | S | S | S |
| Multiple modes | S | S | S | S | S | S | S | S | S | 31.6 | 17.6 | 12.5 |
| Parcel, USPS or courier | S | 45.7 | S | S | 43.1 | S | S | S | S | 31.6 | 18.5 | 13.2 |
| Truck and rail | – | S | S | – | S | S | – | S | S | – | 31.6 | – |
| Other multiple modes | – | S | S | – | S | S | – | S | S | – | 31.6 | – |
| Other and unknown modes | S | S | S | S | S | S | S | S | S | 30.9 | S | S |
SCTG 06-09, Grains, alcohol, and tobacco products
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 12.9 | 13.9 | 40.3 | 19.3 | 19.5 | 61.7 | 21.9 | 20.9 | 61.9 | S | 30.3 | S |
| Single modes | 12.3 | 13.9 | 39.6 | 15.6 | 19.5 | 53.3 | 21.8 | 20.9 | 62.2 | S | 15.4 | S |
| Truck | 13.5 | 14.2 | 41.3 | 14.2 | 20.3 | 51.3 | 26.2 | 25.9 | 72.2 | S | 15.4 | S |
| Rail | 48.3 | 48.8 | 205.8 | S | 41.8 | S | 46.9 | 33.0 | 150.1 | 26.9 | 26.7 | 30.3 |
| Water | – | – | – | – | – | – | – | – | – | – | – | – |
| Air (including truck and air) | – | – | – | – | – | – | – | – | – | – | – | – |
| Pipeline | – | – | – | – | – | – | S | S | S | S | S | S |
| Multiple modes | S | 40.1 | S | 49.0 | 35.3 | 20.0 | 41.2 | 44.5 | 6.3 | 31.5 | 11.5 | 15.3 |
| Parcel, USPS or courier | S | 40.1 | S | 49.0 | 35.3 | 20.0 | 41.2 | 44.5 | 6.3 | 31.5 | 11.5 | 15.3 |
| Truck and rail | – | – | – | – | – | – | – | – | – | – | – | – |
| Other multiple modes | – | – | – | – | – | – | – | – | – | – | – | – |
| Other and unknown modes | S | 34.1 | S | S | 48.1 | S | S | S | S | S | S | S |
SCTG 10-14, Stones, non-metallic minerals, and metallic ores
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 20.3 | S | S | 21.9 | 35.8 | 38.5 | 34.3 | 20.4 | 51.7 | 17.0 | 27.4 | 32.5 |
| Single modes | 20.3 | S | S | 21.9 | 37.2 | 41.4 | 34.3 | 20.7 | 52.6 | 17.8 | 25.0 | 29.4 |
| Truck | 23.9 | S | S | 20.3 | 40.0 | 32.8 | 20.5 | 32.6 | 24.8 | 18.1 | 22.9 | 21.8 |
| Rail | 40.1 | 22.5 | 18.0 | S | 24.5 | S | S | 21.0 | S | 29.7 | 15.0 | 18.3 |
| Water | S | – | S | S | – | S | S | – | S | 31.6 | – | – |
| Air (including truck and air) | – | – | – | – | – | – | – | – | – | – | – | – |
| Pipeline | – | – | – | – | – | – | S | S | S | S | S | S |
| Multiple modes | S | – | S | S | – | S | S | – | S | 31.6 | 31.6 | 31.1 |
| Parcel, USPS or courier | S | S | S | S | S | S | S | S | S | 31.6 | 31.6 | 326.1 |
| Truck and rail | – | – | – | – | – | – | – | – | – | – | – | – |
| Other multiple modes | – | – | – | – | – | – | – | – | – | – | 33.3 | – |
| Other and unknown modes | S | S | S | S | S | S | S | S | S | 29.9 | S | S |
SCTG 15-19, Coal and petroleum products
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 16.5 | 13.9 | 22.9 | 13.1 | 10.1 | 13.9 | 13.9 | 15.2 | 14.4 | 18.3 | 14.3 | 22.0 |
| Single modes | 16.7 | 14.4 | 23.1 | 14.8 | 9.8 | 13.8 | 14.1 | 15.3 | 15.0 | 18.5 | 14.4 | 22.2 |
| Truck | 18.3 | 17.1 | 28.5 | 18.6 | 16.3 | 21.5 | 18.3 | 27.5 | 26.0 | 19.3 | 16.0 | 24.4 |
| Rail | 16.6 | 14.6 | 15.1 | 20.4 | 14.2 | 20.0 | 22.5 | 15.3 | 23.9 | 17.7 | 15.8 | 15.5 |
| Water | S | S | S | S | S | S | S | S | S | S | 28.3 | S |
| Air (including truck and air) | – | – | – | – | – | – | – | – | – | – | – | – |
| Pipeline | – | S | S | – | S | S | S | S | S | S | S | S |
| Multiple modes | S | S | S | S | S | S | S | S | S | 31.6 | 31.1 | 312.8 |
| Parcel, USPS or courier | – | S | S | – | S | S | – | S | S | – | 31.6 | – |
| Truck and rail | – | S | S | – | S | S | – | S | S | – | 31.6 | – |
| Other multiple modes | S | – | S | S | – | S | S | – | S | 31.6 | – | – |
| Other and unknown modes | 43.2 | S | S | S | S | S | 43.7 | S | S | 28.0 | 24.8 | 34.9 |
SCTG 20-24, Pharmaceutical and chemical products
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 9.8 | 8.8 | 20.3 | 27.4 | 23.7 | 55.7 | 38.6 | 24.7 | 92.0 | 14.0 | 14.3 | 37.2 |
| Single modes | 12.3 | 10.5 | 24.7 | 27.5 | 24.9 | 59.7 | 38.8 | 26.5 | 100.8 | 24.5 | 23.3 | 55.7 |
| Truck | 13.8 | 6.2 | 27.3 | 30.5 | 8.7 | 70.4 | 44.5 | 9.2 | 136.3 | 25.1 | 24.4 | 58.7 |
| Rail | 26.4 | 41.0 | 26.4 | 29.5 | 40.1 | 55.8 | S | 42.9 | S | 17.3 | 24.4 | 56.3 |
| Water | S | S | S | S | S | S | S | S | S | 31.5 | 28.7 | 25.9 |
| Air (including truck and air) | S | 49.7 | S | S | 34.5 | S | S | S | S | 25.9 | 11.2 | 33.8 |
| Pipeline | S | S | S | S | S | S | S | S | S | S | S | S |
| Multiple modes | 38.2 | 25.0 | 114.9 | 17.2 | 15.1 | 26.7 | 20.1 | 29.7 | 68.1 | 10.4 | 10.8 | 24.2 |
| Parcel, USPS or courier | 39.5 | 28.9 | 131.4 | 38.3 | 29.5 | 48.2 | 34.9 | 27.2 | 68.2 | 10.7 | 11.1 | 25.0 |
| Truck and rail | 29.4 | S | S | 30.6 | 33.6 | 51.6 | 28.9 | 44.4 | 99.4 | 17.3 | 26.5 | 51.5 |
| Other multiple modes | S | – | S | S | – | S | S | – | S | 30.6 | – | – |
| Other and unknown modes | S | 26.7 | S | S | 43.0 | S | S | 45.1 | S | S | S | S |
SCTG 25-30, Logs, wood products, and textile and leather
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 28.3 | 9.4 | 37.8 | 24.5 | 15.9 | 26.9 | 12.9 | 14.5 | 16.7 | 10.2 | 11.3 | 15.1 |
| Single modes | 28.9 | 9.2 | 38.9 | 24.6 | 16.3 | 27.8 | 13.0 | 14.9 | 17.6 | 9.9 | 13.2 | 15.7 |
| Truck | 31.3 | 9.0 | 43.2 | 29.1 | 18.5 | 33.6 | 11.2 | 10.7 | 15.5 | 10.6 | 13.8 | 16.1 |
| Rail | 13.7 | 16.1 | 20.2 | 18.4 | 19.8 | 21.6 | 17.9 | 25.1 | 23.3 | 4.3 | 7.0 | 8.3 |
| Water | – | – | – | – | – | – | – | – | – | – | – | – |
| Air (including truck and air) | S | 43.9 | S | 47.2 | S | S | 42.0 | S | S | 23.4 | 25.3 | 63.4 |
| Pipeline | – | – | – | – | – | – | S | S | S | S | S | S |
| Multiple modes | 39.3 | 29.3 | 44.3 | 37.3 | S | S | 42.3 | 41.8 | 5.9 | 10.7 | 9.3 | 16.0 |
| Parcel, USPS or courier | 39.4 | 35.3 | 55.3 | 40.8 | 42.2 | 55.2 | 46.0 | 48.6 | 50.2 | 10.8 | 9.3 | 16.1 |
| Truck and rail | S | 31.3 | S | S | S | S | S | 47.7 | S | 31.6 | 19.5 | 22.4 |
| Other multiple modes | S | – | S | S | – | S | S | – | S | 30.8 | – | – |
| Other and unknown modes | 30.7 | 38.8 | 73.4 | 39.6 | 37.2 | 5.7 | 39.2 | 50.0 | 7.0 | S | 25.2 | S |
SCTG 31-34, Base metal and machinery
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 25.1 | 3.3 | 28.2 | 34.3 | 4.9 | 42.6 | 47.7 | 11.2 | 93.5 | 15.2 | 8.4 | 22.8 |
| Single modes | 26.7 | 4.1 | 29.5 | 35.7 | 5.6 | 43.8 | 47.9 | 10.1 | 96.9 | 12.6 | 9.7 | 22.3 |
| Truck | 18.4 | 4.5 | 18.2 | 29.3 | 9.0 | 28.2 | 35.5 | 4.9 | 46.2 | 15.4 | 10.1 | 25.2 |
| Rail | S | 18.6 | S | S | 20.2 | S | S | 27.9 | S | 16.2 | 12.5 | 19.7 |
| Water | S | S | S | S | S | S | S | S | S | 34.0 | 30.0 | 47.1 |
| Air (including truck and air) | S | 37.9 | S | 46.0 | S | S | S | S | S | 16.4 | 6.5 | 21.6 |
| Pipeline | – | S | S | – | S | S | S | S | S | S | S | S |
| Multiple modes | 31.9 | 19.7 | 45.3 | 20.3 | 27.4 | 33.1 | 22.0 | 34.0 | 54.9 | 16.7 | 13.3 | 24.6 |
| Parcel, USPS or courier | 33.0 | 19.5 | 47.9 | 19.0 | 28.7 | 36.8 | 24.6 | 18.7 | 44.0 | 16.8 | 13.3 | 24.7 |
| Truck and rail | 40.2 | S | S | 41.6 | S | S | 38.7 | S | S | 45.5 | 26.1 | 34.7 |
| Other multiple modes | – | S | S | – | S | S | – | S | S | – | 31.6 | – |
| Other and unknown modes | 30.0 | 21.6 | 66.6 | S | 35.1 | S | 31.7 | S | S | 49.5 | 40.9 | 78.4 |
SCTG 35-38, Electronic, motorized vehicles, and precision instruments
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 12.1 | 11.7 | 19.0 | 16.8 | 11.1 | 27.9 | 18.5 | 13.5 | 27.0 | 36.2 | 13.3 | 22.1 |
| Single modes | 16.6 | 15.2 | 26.0 | 16.8 | 11.7 | 25.3 | 19.7 | 14.9 | 30.2 | S | 18.4 | S |
| Truck | 14.2 | 16.8 | 22.0 | 18.9 | 10.4 | 25.1 | 18.5 | 13.2 | 24.3 | S | 18.2 | S |
| Rail | 47.8 | S | S | 47.8 | 46.8 | 159.7 | 49.4 | 41.1 | 144.3 | S | 28.4 | S |
| Water | – | – | – | – | – | – | – | – | – | – | – | – |
| Air (including truck and air) | 49.7 | 23.8 | 28.2 | S | 21.9 | S | S | 20.3 | S | 7.2 | 8.0 | 15.2 |
| Pipeline | – | – | – | – | – | – | S | S | S | S | S | S |
| Multiple modes | 29.7 | 18.4 | 37.9 | S | 16.6 | S | 45.0 | 18.9 | 43.8 | 18.6 | 13.3 | 17.5 |
| Parcel, USPS or courier | 29.8 | 18.7 | 38.5 | S | 19.6 | S | S | 23.3 | S | 18.7 | 13.3 | 17.5 |
| Truck and rail | S | 38.9 | S | S | 36.0 | S | S | 37.4 | S | 29.9 | 20.1 | 33.2 |
| Other multiple modes | – | – | – | – | – | – | – | – | – | – | – | – |
| Other and unknown modes | 43.4 | 30.6 | 52.3 | S | 30.2 | S | 39.9 | 34.7 | 49.8 | S | S | S |
SCTG 39-43, Furniture, mixed freight and misc manufactured products
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 12.3 | 18.6 | 33.4 | 21.3 | 12.2 | 28.0 | 11.8 | 12.5 | 16.5 | 10.1 | 9.5 | 18.3 |
| Single modes | 13.8 | 19.2 | 34.4 | 19.9 | 12.2 | 25.3 | 11.9 | 13.0 | 16.9 | 13.9 | 12.3 | 27.4 |
| Truck | 13.7 | 19.6 | 34.8 | 19.9 | 12.2 | 27.6 | 12.0 | 12.8 | 18.5 | 21.3 | 13.1 | 25.5 |
| Rail | S | 44.0 | S | S | S | S | S | S | S | 41.4 | 27.3 | 106.7 |
| Water | – | 43.9 | – | – | S | S | – | S | S | – | 26.7 | – |
| Air (including truck and air) | S | S | S | 35.8 | 44.5 | 128.0 | 44.8 | 45.9 | 209.6 | 28.6 | 8.4 | 41.1 |
| Pipeline | – | – | – | – | – | – | S | S | S | S | S | S |
| Multiple modes | 24.3 | 15.3 | 56.1 | 14.8 | 15.8 | 25.3 | 23.1 | 29.3 | 35.0 | 10.1 | 6.4 | 13.6 |
| Parcel, USPS or courier | 24.3 | 15.5 | 59.7 | 15.2 | 14.5 | 33.7 | 19.4 | 15.3 | 38.8 | 10.1 | 6.5 | 13.6 |
| Truck and rail | – | 37.5 | – | – | 38.4 | – | – | S | S | – | 26.1 | – |
| Other multiple modes | S | – | S | S | – | S | S | – | S | 31.6 | – | – |
| Other and unknown modes | 40.7 | 28.0 | 162.2 | S | 17.5 | S | 41.9 | 36.6 | 72.7 | S | S | S |
Commodity Unknown
| Mode of transportation | Value | Tons | Ton-miles | Average miles per shipment | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 |
CV 2002 |
CV 1997 |
Std. error of percent change 1997-2002 | |
| All modes | 47.3 | S | S | 41.6 | S | S | S | S | S | 23.8 | 36.9 | 93.8 |
| Single modes | 49.2 | S | S | 41.6 | S | S | S | S | S | S | 20.0 | S |
| Truck | 49.0 | S | S | 26.9 | 49.5 | 28.8 | S | S | S | S | 20.5 | S |
| Rail | S | S | S | S | S | S | S | S | S | 31.6 | 31.6 | 25.7 |
| Water | – | – | – | – | – | – | – | – | – | – | – | – |
| Air (including truck and air) | – | S | S | – | S | S | – | S | S | – | 30.1 | – |
| Pipeline | – | – | – | – | – | – | S | S | S | S | S | S |
| Multiple modes | S | S | S | 41.6 | S | S | 37.8 | 44.6 | 44.0 | S | S | S |
| Parcel, USPS or courier | S | S | S | 41.6 | S | S | 37.8 | 44.6 | 44.0 | S | S | S |
| Truck and rail | – | – | – | – | – | – | – | – | – | – | – | – |
| Other multiple modes | – | – | – | – | – | – | – | – | – | – | – | – |
| Other and unknown modes | S | S | S | S | S | S | S | S | S | 31.6 | 38.7 | 0.7 |
KEY:
– Represents data cell equal to zero or less than 1 unit of measure.
S Estimate does not meet publication standards because of high sampling variability or poor response quality.
CV Coefficient of variation of number
NOTE: The Introduction and appendixes give information onf confidentiality protection, sampling error, nonsampling error, sample design, and definitions. Links to this information on the Internet may be found at www.census.gov/cfs.
SOURCE: Bureau of Transportation Statistics (USDOT) and U.S. Census Bureau, 2002 Commodity Flow Survey, Individual State Data, December 2004.