Basic Functions
Intermediate

ABS for a percentage error

How wrong was the forecast, ignoring which way it was wrong?

Task:

You are reviewing last quarter's demand forecast. For each product, put the size of the forecast error as a share of actual demand in D2:D5 — a miss of 10% is a miss of 10% whether the forecast was high or low.

Interactive Spreadsheet

Read about ABS

Hints

+5 XPno-hints bonus

Solve it on your own to keep the bonus. Each hint gets one step closer to the formula.

Variations of ABS

0/3

The same formula in the other shapes it takes at work.

  1. ABS Function

    How far off you are, not which direction.

    Core
    Beginner
  2. ABS for a tolerance check

    Too high and too low are the same problem: too far from the target.

    Intermediate
  3. ABS for a percentage error

    How wrong was the forecast, ignoring which way it was wrong?

    Intermediate

The data in this exercise

This is the grid you start with. Cell references in the task — B6, C2 — point at the row numbers and column letters below.

5 rows × 4 columns4 cells you fill in
ABCD
1ProductForecastActualError %
2Kettles12001350
3Toasters900810
4Blenders450450
5Irons600750
What this exercise teachesMay contain the answer

Averaging signed errors lets an over-forecast cancel an under-forecast, and a forecast can look perfect while being wrong on every line. Absolute percentage error keeps every miss positive, so a bad forecast always looks bad.