One of the easiest methods in Technical Analysis is the Simple Moving Average or SMA. It is the simplest type of all the moving average. The SMA shows the average price of a given time period. And each period carries the same weight for the average. SMA helps to smooth the price curve for better trend identification. In fact, the longer the SMA period selected, the smoother the curve.
Since it is the simplest of all the moving average, the math behind SMA is also simple. The average price of a certain period is represented by SMA and it is calculated by summing up the prices of instrument closure over a certain number of single periods divided by the number of time periods. Take note that short-term averages respond quickly to changes in the price of the underlying, while long-term averages are slow to react.
SMA = SUM (CLOSE (i), N) / N
Where:SUM - sum; CLOSE (i) - current period closing price; N = number of periods in calculation.
For example you want to plot a 5 period simple moving average on a 1-hour chart, you should add up the closing prices for the last 5 hours and then divide it by 5. If you want to plot 5 period simple moving an average on a 30 minute chart, then you should add up the closing prices of the last 150 minutes and divide it by 5. So if you want to develop an SMA chart for USD/JPY closing price in a 5-day time frame, how would you do it?
For example the first 5 days USD/JPY closing prices are 125.0, 124.0, 126.0, 123.0, and 127.0. The average of the first 5 days USD/JPY closing price that will be the first dots of the SMA graph is 125.0. The second SMA point will be (124.0 + 126.0 + 123.0 + 127.0 + 126.0)/5= 125.2 if we assume the USD/JPY closing price for the day six is 126.0. So the calculation goes on for the following dots. And joining these SMA dots defines the SMA chart. In other words, SMA is the average stock price over a certain period of time.
Formula for the 5 period SMA 5 period SMA = (Price1 + Price2 + Price3 + Price4 + Price5) / 5
Simple Moving Average operates with a delay just like any indicator. You are forecasting of the future price, not a concrete view of the future, because you are just taking the averages of the price. Although all calculations will be provided by most charting packages, it is important to understand how simple moving averages are calculated. By understanding, you can decide on which type of tool is best for you.