| Properties Tables [Table Text Block] |
The following tables list the major categories of property and equipment, as well as the weighted average composite depreciation rate for each category: | Millions, Except Percentages | | Accumulated | Net Book | Depreciation | | As of June 30, 2011 | Cost | Depreciation | Value | Rate for 2011 | | Land | $ | 5,008 | $ | N/A | $ | 5,008 | N/A | | Road: | | | | | | | | | Rail and other track material [a] | | 12,221 | | 4,506 | | 7,715 | 3.3% | | Ties | | 7,814 | | 1,944 | | 5,870 | 2.9% | | Ballast | | 4,081 | | 969 | | 3,112 | 3.0% | | Other [b] | | 13,783 | | 2,437 | | 11,346 | 2.6% | | Total road | | 37,899 | | 9,856 | | 28,043 | 2.9% | | Equipment: | | | | | | | | | Locomotives | | 6,198 | | 2,817 | | 3,381 | 5.7% | | Freight cars | | 1,926 | | 1,059 | | 867 | 3.5% | | Work equipment and other | | 443 | | 42 | | 401 | 5.6% | | Total equipment | | 8,567 | | 3,918 | | 4,649 | 5.2% | | Technology and other | | 571 | | 253 | | 318 | 12.7% | | Construction in progress | | 890 | | - | | 890 | N/A | | Total | $ | 52,935 | $ | 14,027 | $ | 38,908 | N/A | | | | | | | | | | | | [a] | Includes a weighted-average composite depreciation rate for rail in high-density traffic corridors. | | | | | | | | | | | | [b] | Other includes grading, bridges and tunnels, signals, buildings, and other road assets. |
| Millions, Except Percentages | | Accumulated | Net Book | Depreciation | | As of December 31, 2010 | Cost | Depreciation | Value | Rate for 2010 | | Land | $ | 4,984 | $ | N/A | $ | 4,984 | N/A | | Road: | | | | | | | | | Rail and other track material [a] | | 11,992 | | 4,458 | | 7,534 | 3.1% | | Ties | | 7,631 | | 1,858 | | 5,773 | 2.8% | | Ballast | | 4,011 | | 944 | | 3,067 | 3.0% | | Other [b] | | 13,634 | | 2,376 | | 11,258 | 2.5% | | Total road | | 37,268 | | 9,636 | | 27,632 | 2.8% | | Equipment: | | | | | | | | | Locomotives | | 6,136 | | 2,699 | | 3,437 | 5.6% | | Freight cars | | 1,886 | | 1,040 | | 846 | 3.6% | | Work equipment and other | | 305 | | 39 | | 266 | 4.0% | | Total equipment | | 8,327 | | 3,778 | | 4,549 | 5.1% | | Technology and other | | 565 | | 241 | | 324 | 13.2% | | Construction in progress | | 764 | | - | | 764 | N/A | | Total | $ | 51,908 | $ | 13,655 | $ | 38,253 | N/A | | | | | | | | | | | | [a] | Includes a weighted-average composite depreciation rate for rail in high-density traffic corridors. | | | | | | | | | | | | [b] | Other includes grading, bridges and tunnels, signals, buildings, and other road assets. |
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