Reducing Balance Method of Depreciation:

Cost of asset 1,000 Depreciation:   1st year: 10% of 1,000 100   Book value 900 2nd year: 10% of 900 90   Book value 810 3rd year: 10% of 810 81   Book value 729     and so on.......

Under fixed installment method the amount of annual depreciation remains the same but under reducing balance method the amount of annual depreciation gradually reduces.

This method is especially suitable to assets with long life, e.g., plant and machinery, furniture, motor car etc.

Under this method the real cost of using an asset is the depreciation and repair expenses so this method gives better results because in early years when repair expenses are less the depreciation is more. As the asset gets older repair charges on it increases and the amount of depreciation decreases. So the combined effect of both these costs remain almost constant on the profit and loss of each year.

The great weakness of this method is that it takes very long time to write off an asset to approximately nil, unless a very high rate is used, in which case the burden on earlier years shall be excessive. This method is used by income tax authorities for granting depreciation allowance to assesses.

Formula for the Calculation of Depreciation Rate:

The calculation of correct rate of depreciation is very important under this method. Following formula should be applied under given conditions:

When the cost of asset, residual value and useful life of an asset is given:

r = 1 - (S/C)1/n Where: r = Rate of depreciation n = Estimated useful life of asset S = Residual value after the expiry of useful life C = Original cost of asset

Example 2:

If n = 3 years, S = 64,000 and C = 1,000,000 calculate rate of depreciation.

r = 1 - (64,000/1,000,000)1/3 = 1 - 40/100 = 60/100 = 60%

Difference Between Straight Line Method and Reducing Balance Method:

Following are the main points of difference between straight line method and reducing balance method of depreciation:

Straight Line Method		Reducing Balance Method
1.	The rate and amount of depreciation remain the same each year.	1.	The rate remains the same, but the amount of depreciation diminishes gradually.
2.	Depreciation rate per cent is calculated on cost of assets each year	2.	Depreciation rate per cent is calculated on book value of asset.
3.	At the end of its life the value of asset is reduced to zero or scrap value.	3.	The value of asset is never reduced to zero at the end of its life.
4.	The older the asset the larger the cost of its repair. But the amount of depreciation remain the same each year. Hence, the total of depreciation and repairs increases every year. This reduces annual profit gradually.	4.	The amount of depreciation decreases gradually, while the cost of repairs increases. So the total of depreciation and repairs remain more or less the same each year. Hence, it causes little or no change in annual profit/loss.
5.	Computation of depreciation under straight line method is comparatively easy and simple.	5.	Depreciation can be computed without any difficulty, but it is not easy and simple.