Momentum Indicators: Stochastics

Discover stochastics, a technical indicator that enables you to identify the end of one trend and the beginning of another. We’ll explain what the stochastic oscillator is, and how you can use it to anticipate market turning points.

Technical Momentum Indicators Explained

Momentum is an aspect of technical analysis. You can visualise how it works if you imagine a ball being throw in the air.

The velocity (or upside momentum) of the ball begins to slow as it nears the peak of its upward trajectory. That means its upside momentum can be in decline even while the ball is still rising, and subsequently before it begins to fall.

The lesson for technical analysis is that momentum can change direction before the price does, making it an indicator of coming change in market direction.

What is the Stochastic Oscillator?

The Stochastic Oscillator is an indicator of momentum in the movement of a price. It compares where the price is trading relative to the price range (high to low) over a given period. The basic premise behind it is that in an uptrend, the price should be closing near the highs of the period trading range, signalling upward momentum.

In a strong positive market, the bulls should be “winning” the sessions.
Whereas when the price is in a downtrend, strong bearish momentum should come with the price closing near the lows of the trading range.

Deviations from these rules are considered to be signals.

The Stochastic Oscillator was first developed in 1957 by a group of futures traders led by George C. Lane. Lane contributed significantly to the acceptance and popularity of the stochastic oscillator as a technical indicator.

Fast Stochastics and Slow Stochastics

There are two different types of Stochastic Oscillator: Fast and Slow. The Fast Stochastic Oscillator consists of two lines:

%K (the Main Line) = is the raw measure used to formulate the idea of momentum behind the oscillator. It is the main Stochastics line and is displayed as a solid line
%D (the Signal Line) = this is a moving average of %K and is often shown as a dotted line.

Parameters
Number of periods in the range	14
Number of periods for %D calculation	3
Number of periods for Slow Stochastic %D moving average	3

*These are the accepted parameters, but these can be adjusted to meet the needs of the user.

Fast Stochastics: %K and %D

%K = 100 X (C – Ln) / (Hn – Ln)

C = The latest (or closing) price

H = The highest price over the last n periods

L = The lowest price over the last n periods

H3 = the 3-day sum of (C – Ln)

L3 = the 3-day sum of (Hn -Ln)

Slow Stochastics

Extend this relationship a step further to help smooth it replaces the %K line with the %D line and replaces the %D line with a 3-day moving average of %D

Because Fast Stochastics can be quite volatile, traders will often use Slow Stochastics, which are an extension of the relationship and are designed to reduce volatility. Slow Stochastics also consist of two lines, using %D (as the mainline) and a moving average of %D (as the signal line).

How to read Stochastics

Stochastics are plotted within a range of zero and 100, with 50 as the neutral level. Trigger levels are added to the chart at 20 and 80.

When the Stochastics lines are above 80, the price is considered to be strongly bullish or overbought.
When the Stochastics lines are below 20, the price is considered to be strongly negative or oversold.

The table below shows the basic interpretation of Stochastics:

Stochastics level	Outlook
0 - 20	Very BEARISH, but over-extended
30 - 50 and rising	Unwinding a bearish configuration
50 -70 and rising	Increasingly bullish
80 - 100	Very BULLISH, but over-extended
50 - 70 and falling	Unwinding a bullish configuration
30 - 50 and falling	Increasingly bearish