# 何謂年值法????

Update:

Rating

2. 年值法

將一方案所預期的現金流量，按其折現率（或最低可接受報酬率），轉變成等值的年值當量（Equivalent Uniform Annul Worth）以進行方案的評估，習慣上以AW(Annual Worth)來代表此一當量值，年值的計算方式如下式，實際上只是將計算出來的淨現值，乘上資金回收因子（將現值轉為年值）即可。

公式在這個網站上

http://cc.shu.edu.tw/~ppm/file/t_yukuo02.pdf

AW：年值

A：以初期為基準點的年值

P：現值

N：計畫預期使用壽年

i：折現率

此方法的決策準則為獨立方案評估時，在已知折現率、計畫預期使用壽年後，計算出AW，值若大於零，則該方案值得投資，而若是對於兩個以上互斥的方案評估時，則選擇年值較大的方案。

Annual Worth(年値法)

Many of the expenses a company must meet -- rent, wages, taxes -- occur on a regular periodic basis. It is therefore attractive to present investment options in terms of their equivalent uniform annual cost. The calculations for this approach are simple -- we convert present worth to equivalent annual worth by multiplying by the appropriate conversion factor -- but some care is needed in deciding what period of time to consider.

For example, suppose we have a machine that we purchase for a given cost P, and which we expect to sell after N years for a salvage cost S. What is the equivalent annual cost of the machine? (This number is useful if we want to compare buying the machine outright with renting it for a period.) The equivalent cost is conventionally referred to as capital recovery, and can be calculated from

CR=P(A/P,i,N) - S(A/F,i,N)

where the first term on the right-hand side is known as the capital recovery