IB BM – Sales Forecasting Interactive Simulator

Welcome to the Sales Forecasting simulator

This interactive workbook helps HL students spot the trend, calculate moving averages, plot the line, and extrapolate into the future.

HL unit 4.3

What students should be able to do

Explain what a sales forecast is and why firms use one.
Calculate a 3-point moving average and plot it against the correct period.
Calculate a 4-point moving average, then center it correctly.
Use the trend line to extrapolate future sales.
Evaluate the benefits and limitations of forecasting.

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            Key idea: Raw data can look messy. Moving averages smooth out fluctuations so the underlying trend becomes easier to see.
          

How this simulator works

Start with the drag-and-drop example to place 3-point moving average values in the correct months.
Move to the 3-point moving average practice and type values. As correct answers are entered, points appear on the graph.
Then complete the 4-point centered moving average practice, where the centered trend is plotted.
Finally, drag the forecast handle to extend the line into the future and test your extrapolation.

The core formulas

3-point moving average = (month 1 + month 2 + month 3) ÷ 3

4-point moving average = (month 1 + month 2 + month 3 + month 4) ÷ 4

Centered 4-point MA = (first 4-point MA + next 4-point MA) ÷ 2

Extrapolation means continuing the trend line into the future to help predict future sales.

What is sales forecasting?

Forecasting estimates likely future sales so firms can plan capacity, stock, staffing and finance.

1 concept

Sales forecast: an estimate of likely future sales for a product or business.

Underlying trend: the general direction of the data once short-term fluctuations are smoothed out.

Moving average: a method that averages several time periods together to reduce random ups and downs.

Step 1 Take the first group of periods.

Step 2 Calculate the average.

Step 3 Plot it against the middle period for a 3-point average.

Why a 3-point moving average? It smooths short-term fluctuations while still staying fairly responsive to changes in the data.

Quick check

1. Why do businesses use sales forecasts?

2. A 3-point moving average is plotted against which month?

4-point moving averages, centering, and evaluation

A 4-point average smooths the data even more, but it must be centered before plotting.

2 centering

4-point moving average: an average based on four consecutive periods.

Centering: averaging adjacent 4-point moving averages so the trend can be aligned to a single month.

Extrapolation: extending the trend line into the future to estimate future sales.

Benefits of forecasting

Better financial planning and budgeting
Improved inventory and supply-chain management
Stronger marketing and staffing decisions

Limitations of forecasting

Forecasts depend on historical data, which may no longer hold
External shocks can disrupt the trend
Competitor actions and market changes can make forecasts unreliable

Exam-ready evaluation: Forecasting is useful because it gives a structured basis for planning, but managers must still treat the result with caution because trends can change.

Quick check

1. Why do we center a 4-point moving average?

2. Which is the best evaluation point?

Worked example – drag and drop

VitalJuice Ltd. has the following sales data. Drag the first four 3-point moving average values into the correct month.

3 guided practice

Raw sales data (thousand units)

Jan: 120 | Feb: 132 | Mar: 138 | Apr: 150 | May: 168 | Jun: 182

Remember: a 3-point moving average is plotted against the middle month.

Feb

Mar

Apr

May

3-MA

Drop value

130

140

152

166.67

Practice 1 – 3-point moving average

Type each 3-point moving average. When an answer is correct, the point appears on the graph automatically.

4 full practice

VitalJuice monthly sales data

All values are in thousand units.

Jan: 120 Feb: 132 Mar: 138

Apr: 150 May: 168 Jun: 182

Jul: 176 Aug: 188 Sep: 204

Oct: 216 Nov: 228 Dec: 246

Enter the 3-point moving averages

The first one is plotted against Feb. The last one is plotted against Nov.

Extrapolation

Once all 3-point values are correct, drag the forecast handle on the graph to extend the trend into the next 3 months.

Interpretation

The moving average shows the smoothed trend is generally upward, so sales appear to be increasing over time. The moving average proves sales will never fall in the future. The moving average removes the need to look at any raw sales data.

Evaluation

Forecasting is useful for planning, but outside shocks or changes in demand could still make the forecast inaccurate. Once a moving average has been calculated, the business no longer needs judgement. A moving average is only useful if every month is identical.

Practice 2 – 4-point centered moving average

First calculate the 4-point moving averages, then the centered values. Correct centered values appear on the graph.

5 full practice

VitalJuice monthly sales data

Use the same raw sales data as before. Calculate the 4-point averages first, then center them.

Jan: 120 Feb: 132 Mar: 138

Apr: 150 May: 168 Jun: 182

Jul: 176 Aug: 188 Sep: 204

Oct: 216 Nov: 228 Dec: 246

Step 1 – 4-point moving averages

These fall between months.

Step 2 – Center the averages

These centered values can be plotted against Feb to Sep.

Extrapolation

After all centered values are correct, drag the forecast handle to continue the trend.

Interpretation

The centered moving average gives a smoother picture of the underlying trend than the raw data alone. A 4-point moving average should be plotted without centering because that is more precise. Once centered values are plotted, raw sales no longer matter at all.

Evaluation

A smoother trend helps with planning, but forecasts can still be undermined by inflation, market shifts, or competitor actions. A 4-point moving average guarantees future demand because it uses more months. Forecasting only matters for businesses that never face uncertainty.

Flashcard studio

Click the card to flip it. Use the jump list to move between terms.

6 retrieval

Topic

Term

Tap / click to reveal the definition.

Topic

Definition

Definition goes here.

End-of-topic quiz

Choose an answer and it will be checked instantly.

7 quiz

Question 1 of 10

Score: 0 / 10

Select, get feedback, then move on.

IB Business Management HL – Sales Forecasting

Welcome to the Sales Forecasting simulator

What is sales forecasting?

4-point moving averages, centering, and evaluation

Worked example – drag and drop

Raw sales data (thousand units)

Practice 1 – 3-point moving average

VitalJuice monthly sales data

Enter the 3-point moving averages

Extrapolation

Practice 2 – 4-point centered moving average

VitalJuice monthly sales data

Step 1 – 4-point moving averages

Step 2 – Center the averages

Extrapolation

Flashcard studio

End-of-topic quiz

Quiz complete