What Is the Standard Deviation Indicator

Twenty closes, and how far each sits from their average

The standard deviation indicator is one number for how scattered the last twenty closes have been. Take the twenty closes, find their average, and measure how far each close sits from it: for gold's twenty days to 18 July 2025 the average was 3331.12, the furthest close sat 58 dollars under it and the highest 37 over, and most were within twenty. Fold those twenty distances into one typical distance and the answer is 21.51 dollars. That is the reading, in the price's own units.

Darts round a bullseye

The picture is a dartboard. The bullseye is the average of the last twenty closes, and each dart is one of those closes, landing as far from the centre as that close sat from the average. A tight group gives a small number; a wide group gives a large one. Standard deviation is the spread of the darts written as one number, the typical distance from the centre. It says nothing about where the board hangs on the wall, only how scattered the throws were.

This paper is locked