Plant Depreciation

Plant Depreciation

Overview

Depreciation refers to the gradual reduction in the value of physical assets, such as machinery and equipment, over time due to wear and tear, usage, obsolescence, or age. It is an accounting method used to allocate the cost of these long-term assets over their useful life, reflecting the asset's decreasing value in financial statements. Within Workbench, Plant Depreciation applies this concept specifically to plant items.

This is a step in the Month End process and is only applied when depreciation costs are calculated within the system. Workbench uses the details of each Plant Item to calculate its monthly depreciation cost. These costs are recorded as Disbursement transactions in a Disbursement batch.

Plant depreciation can be applied for:

  • All plants

  • A particular plant item

  • A plant group.

 

Depreciation methods

Workbench supports both two common approaches to calculating depreciation: Diminishing Value Method and Straight-Line Method. Organisation can choose the best fitted method.

 

A. Diminishing Value Method: Depreciation is calculated as a fixed percentage of the asset’s book value (remaining value) at the beginning of each year. Characteristics:

  • Depreciation is higher in the earlier years and decreases over time.

  • This method reflects assets losing more value when they are newer or used more heavily.

  • Suitable for assets like machinery or vehicles that lose value rapidly in the initial years.

  • Formula: Depreciation cost = Depreciation Rate × Book Value at the Beginning of the Year.

B. Straight-Line Method: Depreciation is spread evenly over the asset’s useful life, so the same amount is deducted each year. Note that this method requires defining the useful life of the plant item for calculation. Characteristics:

  • Provides a consistent depreciation expense each month.

  • Simple and easy to apply.

  • Often used for assets like buildings or office equipment, where the asset’s use is fairly consistent over time.

  • Formula: Depreciation Expense = Cost of Asset/ Useful Life.

 

Example:

Scenario:

  • Asset: A Plant Item

  • Cost of Asset: $10,000

  • Useful Life: 5 years


A. Diminishing Value Method

In this method, depreciation is calculated as a fixed percentage of the book value at the start of each year.

  • Depreciation Rate: 20%

  • Depreciation Schedule:

Year

Month

Depreciation Cost

Accumulated Depreciation

Book Value

Year

Month

Depreciation Cost

Accumulated Depreciation

Book Value

1

1

$166.67 (20% of $10,000 / 12)

$166.67

$9,833.33

 

2

$166.67

$333.34

$9,666.66

 

3

$166.67

$500.01

$9,500.00

 

4

$166.67

$666.68

$9,333.33

 

5

$166.67

$833.35

$9,166.66

 

6

$166.67

$1,000.02

$9,000.00

 

7

$151.67 (20% of $9,000 / 12)

$1,151.69

$8,848.33

 

8

$147.47

$1,299.16

$8,700.86

 

9

$143.35

$1,442.51

$8,557.51

 

10

$131.67

$1,574.18

$8,425.84

 

11

$129.36

$1,703.54

$8,296.48

 

12

$126.21

$1,829.75

$8,170.27

2

1

$118.10 (20% of $8,170.27 / 12)

$1,947.85

$8,052.17

 

2

$113.40

$2,061.25

$7,938.77

 

3

$109.28

$2,170.53

$7,829.49

 

4

$105.14

$2,275.67

$7,724.36

 

5

$102.19

$2,377.86

$7,622.17

 

6

$99.03

$2,476.89

$7,523.14

 

7

$96.10

$2,572.99

$7,427.04

 

8

$93.09

$2,666.08

$7,333.95

 

9

$90.07

$2,756.15

$7,243.88

 

10

$87.08

$2,843.23

$7,156.80

 

11

$84.14

$2,927.37

$7,072.66

 

12

$81.06

$3,008.43

$6,991.60

3

1

$75.00 (20% of $6,991.60 / 12)

$3,083.43

$6,916.60

 

2

$69.03

$3,152.46

$6,847.57

 

3

$65.09

$3,217.55

$6,782.48

 

4

$61.11

$3,278.66

$6,721.37

 

5

$57.33

$3,335.99

$6,664.04

 

6

$53.73

$3,389.72

$6,610.31

 

7

$50.22

$3,439.94

$6,560.09

 

8

$46.80

$3,486.74

$6,513.29

 

9

$43.48

$3,530.22

$6,469.81

 

10

$40.26

$3,570.48

$6,429.55

 

11

$37.13

$3,607.61

$6,392.42

 

12

$34.09

$3,641.70

$6,358.33

4

1

$27.00 (20% of $6,358.33 / 12)

$3,668.70

$6,331.33

 

2

$26.42

$3,695.12

$6,304.91

 

3

$25.84

$3,720.96

$6,279.07

 

4

$25.25

$3,746.21

$6,253.82

 

5

$24.67

$3,770.88

$6,229.15

 

6

$24.09

$3,794.97

$6,205.06

 

7

$23.51

$3,818.48

$6,181.55

 

8

$22.93

$3,841.41

$6,158.62

 

9

$22.36

$3,863.77

$6,136.26

 

10

$21.79

$3,885.56

$6,114.47

 

11

$21.21

$3,906.77

$6,093.26

 

12

$20.63

$3,927.40

$6,072.63

5

1

$20.05 (20% of $6,072.63 / 12)

$3,947.45

$6,052.58

 

2

$19.47

$3,966.92

$6,032.10

 

3

$18.89

$3,985.81

$6,012.38

 

4

$18.31

$4,004.12

$5,994.07

 

5

$17.74

$4,021.86

$5,976.33

 

6

$17.16

$4,038.02

$5,959.17

 

7

$16.58

$4,054.60

$5,942.59

 

8

$16.01

$4,070.60

$5,926.58

 

9

$15.43

$4,086.03

$5,911.15

 

10

$14.86

$4,100.89

$5,896.29

 

11

$14.28

$4,115.17

$5,882.01

 

12

$13.71

$4,128.88

$5,868.30


B. Straight-Line Method

In this method, depreciation is spread evenly over the asset’s useful life.

  • Annual Depreciation:

    Depreciation Cost = Cost of Asset/ Useful Life = 10,000/5=2000 per year

  • Depreciation Schedule:

  • Depreciation Schedule:

 

Year

Month

Depreciation Cost

Accumulated Depreciation

Book Value

Year

Month

Depreciation Cost

Accumulated Depreciation

Book Value

1

1

$166.67

$166.67

$9,833.33

 

2

$166.67

$333.34

$9,666.66

 

3

$166.67

$500.01

$9,500.00

 

4

$166.67

$666.68

$9,333.33

 

5

$166.67

$833.35

$9,166.66

 

6

$166.67

$1,000.02

$9,000.00

 

7

$166.67

$1,166.69

$8,833.33

 

8

$166.67

$1,333.36

$8,666.66

 

9

$166.67

$1,500.03

$8,500.00

 

10

$166.67

$1,666.70

$8,333.33

 

11

$166.67

$1,833.37

$8,166.66

 

12

$166.67

$2,000.04

$8,000.00

2

1

$166.67

$2,166.71

$7,833.33

 

2

$166.67

$2,333.38

$7,666.66

 

3

$166.67

$2,500.05

$7,500.00

 

4

$166.67

$2,666.72

$7,333.33

 

5

$166.67

$2,833.39

$7,166.66

 

6

$166.67

$3,000.06

$7,000.00

 

7

$166.67

$3,166.73

$6,833.33

 

8

$166.67

$3,333.40

$6,666.66

 

9

$166.67

$3,500.07

$6,500.00

 

10

$166.67

$3,666.74

$6,333.33

 

11

$166.67