Calculating a simple moving average one period at a time

The lesson defines a simple moving average as the arithmetic mean of a selected number of prices, commonly closes. A five-period version adds five closing values and divides by five. As a new period arrives, the oldest observation drops out of the window.

The word “period” depends on the chart. Five observations on an hourly chart represent a different interval from five observations on a daily chart. The calculation can be identical while the economic context and apparent responsiveness differ.

An average smooths fluctuations but necessarily uses historical data. A turn in the line can occur after prices have already changed, and a large observation can affect the result until it leaves the window. Record the input field, time frame and length when comparing charts. The moving average is a descriptive calculation, not a guarantee of trend persistence or a standalone investment recommendation.