Depreciation is defined as, "the accounting process of allocating the cost of tangible assets to expense in a systematic and rational manner to those periods expected to benefit from the use of the asset. Depreciation is not a matter of valuation but a means of cost allocation. Assets are not depreciated on the basis of a decline in their fair market value, but on the basis of systematic charges to expense."
PSU uses straight-line depreciation with zero salvage value, and useful lives that vary depending on the type of asset. Refer to the asset type table and /wiki/spaces/~655483049/pages/1001390624 maintained by the Controller's Office.
The /wiki/spaces/~655483049/pages/1001456049 provides additional detail of depreciation policies by account code. The information included is integral to this policy.