GENERAL DYNAMICS CORP | 2013 | FY | 3


PROPERTY, PLANT AND EQUIPMENT, NET
PP&E is carried at historical cost, net of accumulated depreciation. The major classes of PP&E were as follows:
December 31
2012
 
2013
Machinery and equipment
$
3,966

 
$
4,156

Buildings and improvements
2,442

 
2,508

Land and improvements
340

 
337

Construction in process
255

 
247

Total PP&E
7,003

 
7,248

Accumulated depreciation
(3,600
)
 
(3,833
)
PP&E, net
$
3,403

 
$
3,415


We depreciate most of our assets using the straight-line method and the remainder using accelerated methods. Buildings and improvements are depreciated over periods of up to 50 years. Machinery and equipment are depreciated over periods of up to 30 years. Our government customers provide certain facilities and as such, we do not include these facilities above.

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