Understand your numbers

How the calculation works

Mean = sum / n. Median = middle sorted value. Sample variance uses n − 1; population variance uses n. Standard deviation is the square root of variance. Spread is evaluated on range-scaled deviations before converting back to the entered units, preventing squaring tiny raw differences.

Worked example

With value 1 8 units, value 2 12 units, value 3 15 units, value 4 9 units, value 5 16 units, average is 12 units.

Assumptions and limits

Five equally weighted numeric observations. Sample spread estimates a wider population; population spread describes only the entered observations. No inference test or forecast is performed.