Properties

9 Months Ended

Sep. 30, 2020

11. Properties

The following tables list the major categories of property and equipment, as well as the weighted-average estimated useful life for each category (in years):



Millions, Except Estimated Useful Life			Accumulated		Net Book		Estimated
As of September 30, 2020	Cost		Depreciation		Value		Useful Life
Land	$	5,274	$	N/A	$	5,274	N/A
Road:
Rail and other track material		17,521		6,550		10,971	42
Ties		10,997		3,294		7,703	34
Ballast		5,893		1,723		4,170	34
Other roadway [a]		20,759		4,259		16,500	48
Total road		55,170		15,826		39,344	N/A
Equipment:
Locomotives		9,427		3,548		5,879	17
Freight cars		2,082		790		1,292	25
Work equipment and other		1,101		340		761	18
Total equipment		12,610		4,678		7,932	N/A
Technology and other		1,176		508		668	12
Construction in progress		1,157		-		1,157	N/A
Total	$	75,387	$	21,012	$	54,375	N/A



Millions, Except Estimated Useful Life			Accumulated		Net Book		Estimated
As of December 31, 2019	Cost		Depreciation		Value		Useful Life
Land	$	5,276	$	N/A	$	5,276	N/A
Road:
Rail and other track material		17,178		6,381		10,797	42
Ties		10,693		3,186		7,507	34
Ballast		5,752		1,669		4,083	34
Other roadway [a]		20,331		4,056		16,275	48
Total road		53,954		15,292		38,662	N/A
Equipment:
Locomotives		9,467		3,434		6,033	18
Freight cars		2,083		779		1,304	25
Work equipment and other		1,081		322		759	18
Total equipment		12,631		4,535		8,096	N/A
Technology and other		1,136		503		633	12
Construction in progress		1,249		-		1,249	N/A
Total	$	74,246	$	20,330	$	53,916	N/A

[a]Other roadway includes grading, bridges and tunnels, signals, buildings, and other road assets.