Annual Depreciation cost.
There are various methods to calculate depreciation, one of the most commonly used methods is the straight-line method, keeping this method in mind the above formula to calculate depreciation rate (annual) has been derived.
Example
Cost of machine = 10,000, Scrap value of machine = 1,000
Machine’s estimated useful life = 5 years
Annual Depreciation cost = (Cost of Asset – Net Scrap Value)/Useful Life
Annual Depreciation cost = (10,000-1,000)/5
= 9,000/5
= 1,800 per year
Rate % = (Annual Depreciation cost/ Cost of Asset) * 100
(Annual Depreciation in %ge) = (1,800/10,000) * 100 = 18%