McClellan Summation Index RSI

The McClellan Summation Index RSI indicator provides a comprehensive look at market breadth by calculating the McClellan Summation Index (MSI) and applying a Relative Strength Index (RSI) to it to identify broad market trends and potential reversals. By normalizing the cumulative nature of the Summation Index through RSI, this tool allows traders to compare current breadth momentum against historical levels more effectively.

Usage

The script offers two primary modes of operation, selectable via the settings, to suit different trading timeframes:

• MSI RSI Mode: This is the primary mode designed for swing trading over several weeks. It tracks the broad market direction by applying a 14-period RSI to the McClellan Summation Index. Users should look for the RSI to curl up from "Tailwind" levels (e.g., 30) as a potential signal for a market rally. Conversely, a rollover from "Headwind" levels (e.g., 70) can indicate potential market exhaustion.
• McClellan Oscillator (MO) Mode: Intended for short-term or intraday trading, this mode displays the raw McClellan Oscillator along with a moving average. Because it is not a cumulative total, it reacts much faster than the MSI. Traders often look for crossovers between the MO and its moving average or analyze trendlines and horizontal levels for signs of short-term momentum shifts.

Details

The indicator is built upon market breadth data (Advancing vs. Declining issues). It first calculates the "Ratio Adjusted Net Advances" (RANA) and then derives the McClellan Oscillator by taking the difference between the 19-day and 39-day exponential moving averages of that ratio.

The McClellan Summation Index is a running total (cumulative sum) of these Oscillator values. Because a cumulative sum can trend indefinitely, making it difficult to find overbought or oversold extremes, applying an RSI to the Summation Index creates a bounded oscillator that highlights the relative strength of the breadth trend. The script allows users to toggle between Nasdaq, NYSE, or combined exchange data to ensure the breadth calculation matches their specific market focus.

Settings

Main Settings

• Display Type: Choose between "MSI RSI" for long-term trend analysis or "MO" for short-term momentum.
• Head Wind: The overbought/upper threshold for the MSI RSI (default is 70).
• Tail Wind: The oversold/lower threshold for the MSI RSI (default is 30).
• RSI length: The lookback period used for the RSI calculation on the Summation Index.
• Choose Exchange: Select the data source for breadth calculations (NASDAQ, NYSE, or NASDAQ+NYSE).
• MO MA Length: The length of the Moving Average applied to the McClellan Oscillator when in MO mode.

FAQ

How do I use the MSI RSI for trend identification?

The MSI RSI is best used for identifying the broad market regime. When the RSI value is rising and moves out of the "Tailwind" zone, it historically suggests a high probability of a sustained market rally.

What is the difference between MO and MSI?

The McClellan Oscillator (MO) is a momentum indicator that measures the speed of breadth changes, while the McClellan Summation Index (MSI) is a cumulative measure that represents the long-term trend of that breadth.

How can I access this indicator?

You can get access on the LuxAlgo Library for charting platforms like TradingView, MetaTrader (MT4/MT5), and NinjaTrader for free.