week-02

แนวคิดเก่ยี วกบั การบัญชีตนทนุ การวเิ คราะหพ ฤติกรรมตนทุนและเทคนคิ การประมาณตน ทุน

Introduction Cost Cost Costestimation behavior prediction Process of Relationship Using knowledge determining between of cost behaviorcost behavior, cost andoften focusing activity. to forecast on historical level of cost at data. a particular activity. Focus is on the future.

รูปแบบของพฤตกิ รรมตนทุนVariable and Fixed Cost BehaviorCost In Total Per UnitVariable Total variable cost Variable cost per unit changes as activity remains the same level changes. over wide ranges of activity.Fixed Total fixed cost Fixed cost per unit remains the same goes down as activity even when the level goes up. activity level changes.

Step-Variable CostsTotal cost remainsconstant within a narrow range of activity. Cost Activity

Step-Variable Costs Cost Total cost increases to a new higher cost for the next higher range of activity. Activity

Step-Fixed CostsExample: Office spaceis available at a rental rate of$30,000 per year in incrementsof 1,000 square feet. As thebusiness grows more space isrented, increasing the totalcost.

Step-Fixed CostsRent Cost in 90 Thousands of Dollars Total cost doesn’t change for a wide 60 range of activity, and then jumps to a new higher cost for 30 the next higher range of activity. 0 1,000 2,000 3,000 Rented Area (Square Feet)

Step-Fixed CostsHow does this type of Step-variable costs can be adjusted morefixed cost differ from quickly and . . .a step-variable cost? The width of the activity steps is much wider for the step-fixed cost.

Semivariable Cost A semivariable cost is partly fixed and partly variable.

Semivariable Cost Slope is variable cost per unit of activity.Total Utility Cost Variable Utility Charge Fixed Monthly Utility Charge Activity (Kilowatt Hours)

Curvilinear Cost Curvilinear Cost FunctionTotal Cost Straight-Line Approximation (constant unit variable cost) Relevant Range Activity

Curvilinear Cost Curvilinear Cost FunctionTotal Cost A straight line closely approximates a curvilinear variable cost line within the relevant range. Relevant Range Activity

Cost Estimation Account-Classification Method Visual-Fit Method High-Low Method Least-Squares Regression Method Engineering Method of Cost Estimation

Account Classification Method Cost estimates are based on a review of each account making up the total cost being analyzed.

Example Overhead Costs for 1,000 Units Tota l Variable FixedAccount Cost Cost CostIndirect LaborIndirect Material $ 450 $ 450De pre ci a ti onProperty Taxes 700 700InsuranceUtilities 1,000 1,000Ma inte na nce 200 200 Totals 300 300 400 350 50 600 500 100 $ 3,650 $ 2,000 $ 1,650

Visual-Fit Method A scatter diagram of past cost behavior may be helpful in analyzing mixed costs.

Visual-Fit Method Plot the data points on a graph (total cost vs. activity).Total Cost in 20 * * * ** * 1,000’s of Dollars 10 * ** * 0 01234 Activity, 1,000’s of Units Produced

Visual-Fit Method Draw a line through the plotted data points so that about equal numbers of points fall above and below the line.Total Cost in 20 * * * ** * 1,000’s of Dollars 10 * ** * 0 01234 Activity, 1,000’s of Units Produced

Visual-Fit Method Draw a line through the plotted data points so that about equal numbers of points fall above and below the line.Total Cost in 20 * * * ** * 1,000’s of Dollars 10 * ** * 0 01234 Activity, 1,000’s of Units Produced

The High-Low MethodOwlCo recorded the following production activity and maintenance costs for two months:High activity level Units CostLow activity levelCha nge 9,000 $ 9,700 5,000 6,100 4,000 $ 3,600Using these two levels of activity, compute:• the variable cost per unit.• the total fixed cost.

The High-Low MethodHigh activity level Units CostLow activity levelCha nge 9,000 $ 9,700 5,000 6,100 4,000 $ 3,600Unit variable cost = Δ in cost Δ in unitsFixed cost = Total cost – Total variable costFixed cost = $9,700 – ($0.90 per unit × 9,000 units)Fixed cost = $9,700 – $8,100 = $1,600

Equation Form TC = F + VX Total Cost is the The activity (X) is thedependent variable. independent variable. The intercept term (F) is The X term coefficient (V)the estimate of fixed costs. is the estimate of variable cost per unit of activity, the slope of the cost line.

The End