Table B-2c. Estimated Standard Error of Percentage for Export Shipment Characteristics by Domestic Mode: Percent of Total for 2002 and 1997
Monday, July 2, 2012
Table B-2c. Estimated Standard Error of Percentage for Export Shipment Characteristics by Domestic Mode: Percent of Total for 2002 and 1997
[Estimates are shown as percents and are based on data from the 2002 and 1997 Commodity Flow Surveys]
| Domestic mode of transportation | Value | Tons | Ton-miles | |||
|---|---|---|---|---|---|---|
| Std. error of percent 2002 | Std. error of percent 1997 | Std. error of percent 2002 | Std. error of percent 1997 | Std. error of percent 2002 | Std. error of percent 1997 | |
| All modes | – | – | – | – | – | – |
| Single modes | 1.1 | 1.3 | 0.8 | 3.2 | 1.3 | 1.7 |
| Truck | 1.0 | 2.3 | 3.6 | 2.2 | 3.6 | 1.9 |
| Rail | 0.3 | 1.5 | 1.8 | 2.2 | 3.8 | 3.3 |
| Water | 0.7 | 0.5 | 4.1 | 2.7 | 1.9 | 2.1 |
| Air (including truck and air) | 1.0 | 2.4 | – | – | 0.3 | 0.2 |
| Pipeline | S | S | S | S | S | S |
| Multiple modes | 1.0 | 1.0 | 0.8 | 0.3 | 1.4 | 1.8 |
| Parcel, U.S.P.S. or courier | 0.8 | 0.9 | – | – | – | – |
| Truck and rail | 0.3 | 0.3 | 0.6 | 0.2 | 0.7 | 0.7 |
| All other multiple modes | – | – | 0.3 | 0.3 | 1.3 | 1.5 |
| Other and unknown modes | 0.4 | 0.8 | 0.3 | 3.3 | 0.2 | 1.8 |
KEY:
– Represents an estimate 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.
NOTE: The Introduction and appendixes give information on 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: Research and Innovative Technologies Administration, Bureau of Transportation Statistics (USDOT) and U.S. Census Bureau, 2002 Commodity Flow Survey, Export Data, March 2005.