Association of Accounting Technicians (AAT) Principles of Costing (Level 2) Syllabus

Using the high-low method, how do you find the fixed cost once the variable cost per unit is known?

$$\text{Fixed cost} = \text{Total cost} - (\text{Variable cost per unit} \times \text{Activity level})$$ using either the high or low data point.

High-low worked example: total cost is £8,000 at 1,000 units and £12,000 at 3,000 units. Find the variable cost per unit.

$$\frac{12{,}000 - 8{,}000}{3{,}000 - 1{,}000} = \frac{4{,}000}{2{,}000} = \pounds 2 \text{ per unit}$$

Continuing the example (VC = £2/unit, £8,000 at 1,000 units), find the fixed cost.

$$\text{Fixed cost} = 8{,}000 - (2 \times 1{,}000) = 8{,}000 - 2{,}000 = \pounds 6{,}000$$

What is the general formula for total cost in terms of fixed and variable costs?

$$\text{Total cost} = \text{Fixed cost} + (\text{Variable cost per unit} \times \text{Number of units})$$

How is cost per unit calculated?

$$\text{Cost per unit} = \frac{\text{Total cost}}{\text{Number of units produced}}$$

Calculate total cost for 500 units when fixed cost is £4,000 and variable cost is £3 per unit.

$$\text{Total cost} = 4{,}000 + (3 \times 500) = 4{,}000 + 1{,}500 = \pounds 5{,}500$$

For the previous example, what is the total cost per unit at 500 units?

$$\frac{5{,}500}{500} = \pounds 11 \text{ per unit}$$ (made up of £8 fixed per unit + £3 variable per unit).

Why does total cost per unit fall as activity rises (with fixed and variable costs)?

Because the fixed cost element is spread over more units, lowering fixed cost per unit, while variable cost per unit stays the same, so the combined cost per unit decreases.

Name the three main methods of inventory (stock) valuation in AAT costing.

FIFO (First In, First Out), LIFO (Last In, First Out), and AVCO (Weighted Average Cost).

How does the FIFO method value issues and closing inventory?

FIFO assumes the oldest (first received) inventory is issued first, so issues are valued at the earliest prices and closing inventory is valued at the most recent (latest) prices.

How does the LIFO method value issues and closing inventory?

LIFO assumes the newest (last received) inventory is issued first, so issues are valued at the most recent prices and closing inventory is valued at the older prices.

How does the AVCO method value inventory?

AVCO recalculates a weighted average cost per unit after each receipt and values both issues and closing inventory at that average: $$\text{Average cost} = \frac{\text{Total cost of inventory held}}{\text{Total units held}}$$

During a period of rising prices, which method gives the highest closing inventory value and highest profit?

FIFO. Issues are charged at older (lower) prices, so cost of sales is lower and closing inventory (valued at latest higher prices) and profit are higher.

During a period of rising prices, which method gives the lowest closing inventory value and lowest profit?

LIFO. Issues are charged at the latest (higher) prices, so cost of sales is higher and closing inventory and reported profit are lower.

Where does AVCO sit relative to FIFO and LIFO for profit and inventory value during rising prices?

AVCO gives values between FIFO and LIFO, because it smooths price changes by using a weighted average, so its profit and closing inventory fall in the middle.

Why does the choice of inventory valuation method affect reported profit?

Because it changes the value assigned to cost of sales (issues) and to closing inventory. A higher closing inventory value lowers cost of sales and raises profit, and vice versa.

Which inventory valuation method is not permitted under IAS 2 / UK accounting standards for financial reporting?

LIFO is not permitted under IAS 2 for external financial reporting; FIFO and AVCO are acceptable.

What is time-rate (basic hourly) labour payment?

Workers are paid a fixed rate for each hour worked: $$\text{Pay} = \text{Hours worked} \times \text{Rate per hour}$$ It is simple but does not directly reward higher output.

What is overtime, and what is an overtime premium?

Overtime is hours worked beyond normal contracted hours. The overtime premium is the extra amount paid above the basic rate for those hours (e.g. 'time and a half' includes a premium of half the basic rate).

What is a piecework (piece-rate) labour payment system?

Workers are paid a fixed amount for each unit produced: $$\text{Pay} = \text{Units produced} \times \text{Rate per unit}$$ It rewards output/productivity directly.

What is a bonus (incentive) scheme in labour payment?

A scheme paying workers a basic wage plus an additional bonus for output above a target or for time saved against an allowed standard, encouraging higher productivity.

Calculate gross pay: a worker produces 200 units on piecework at £0.75 per unit.

$$200 \times 0.75 = \pounds 150$$

Calculate gross pay: 40 hours at £10/hour plus 5 overtime hours at time-and-a-half.

Basic: $$40 \times 10 = \pounds 400$$. Overtime: $$5 \times (10 \times 1.5) = 5 \times 15 = \pounds 75$$. Gross pay = £475.

Why are spreadsheets useful for handling cost data?

They allow large volumes of data to be stored, sorted, calculated, recalculated automatically with formulas, presented in charts, and quickly updated, reducing manual errors and saving time.

Name common spreadsheet functions used in cost analysis.

SUM, AVERAGE, MAX, MIN, IF, ROUND, and lookup functions such as VLOOKUP; plus cell referencing (absolute $A$1 and relative) for copying formulas.

What is a variance in cost reporting?

The difference between a budgeted (expected) amount and the actual amount: $$\text{Variance} = \text{Budget} - \text{Actual}$$ used to monitor and control performance.

What is the difference between a favourable and an adverse variance?

A favourable (F) variance improves profit (actual cost lower than budget, or actual revenue higher). An adverse (A) variance reduces profit (actual cost higher than budget, or revenue lower).

Budgeted cost £10,000, actual cost £11,500. State the variance and whether it is favourable or adverse.

$$\text{Variance} = 10{,}000 - 11{,}500 = -\pounds 1{,}500$$ — an adverse variance of £1,500 because actual cost exceeded budget.

What is the significance of a percentage variance, and how is it calculated?

It shows the size of a variance relative to budget so managers can judge importance: $$\text{Variance \%} = \frac{\text{Variance}}{\text{Budgeted amount}} \times 100$$

What does 'reporting by exception' mean when reporting cost information to management?

Highlighting only the significant variances (those exceeding a set threshold or percentage) so managers focus attention and time on the items most needing investigation and action.