Let’s say we plot a 5-period SMA on the daily chart of EUR/USD.
The closing prices for the last 5 days are as follows:
On Day 1: 1.3172
Day 2: 1.3231
On Day 3: 1.3164
Day 4: 1.3186
On Day 5: 1.3293
Calculating a Simple Moving Average
We would calculate the simple moving average as follows:
(1.3172 + 1.3231 + 1.3164 + 1.3186 + 1.3293) / 5 = 1.3209
Simple enough, right?
Well, what if there was a news report on Day 2 that causes the euro to drop across the board?
This causes EUR/USD to plunge and close at 1.3000. Let’s see what effect this would have on the 5-period SMA.
Day 1: 1.3172
On Day 2: 1.3000
Day 3: 1.3164
On Day 4: 1.3186
Day 5: 1.3293
We would calculate the simple moving average as follows:
(1.3172 + 1.3000 + 1.3164 + 1.3186 + 1.3293) / 5 = 1.3163
Distorted Results
The result of the simple moving average would be a lot lower and it would give you the notion that the price was actually going down when in reality, Day 2 was just a one-time event caused by the poor results of an economic report.
The point we’re trying to make is that sometimes the simple moving average might be too simple.
If only there was a way that you could filter out these spikes so that you wouldn’t get the wrong idea.
Hmm… Wait a minute… Yep, there is a way!
It’s called the Exponential Moving Average!