In: Economics
A depreciable item is purchased for $500,000. The salvage value at the end of 25 years is
estimated at $100,000. What is the depreciation in each of the first three years using the (a)
straight line, (b) sum-of-the-years' digits, and (c) double-declining balance methods?
a) straight line methods
purchase value = 500000
salvage value = 100000
useful life = 25
Depreciation per year = (500000 - 100000)/25 = 400000/25 = 16000
Depreciation in three years = 3*16000 = 48000
b) Sum of the years digit method
purchase value = 500000
salvage value = 100000
useful life, n = 25
sum of digits over useful life = n*(n+1)/2 = 25*26/2 = 325
Depreciaiton in year m = [(total life - m +1)/ sum of digits ] * (purchase value - salvage value)
Depreciation in first year = (25-1+1)/325 * (500000-100000) = 25/325 * 400000 = 30769.23
Depreciation in second year = (25-2+1)/325 * 400000 = 29538.46
Depreciation in third year = (25-3+1)/325 * 4000000 = 28307.69
Total depreciation = 30769.23+29538.46+28307.69 = 88615.38
c) double declinign methods
purchase value = 500000
salvage value = 100000
useful life = 25
d = 2/25 = 0.08
Depreciation in any year m = purchase value *(1-d)m-1*d
Depreciation in first year = 500000 * (1-0.08)1-1 * 0.08= 500000 * 0.08 = 40000
Depreciation in second year = 500000 * (1-0.08)2-1 * 0.08= 500000 * 0.08*0.92 = 36800
Depreciation in third year = 500000 * (1-0.08)3-1 * 0.08= 500000 * 0.08 * 0.922 = 33856
Total depreciation = 40000 + 36800 + 33856 = 110656