Elder-ray Index

Created by Alexander Elder, the Elder-ray Index, also known as Bull and Bear Power, is an oscillator that depicts buying and selling pressure. It compares current high/low prices against an Exponential Moving Average. [Discuss] 💬

chart for Elder-ray Index

// C# usage syntax
IEnumerable<ElderRayResult> results =


lookbackPeriods int - Number of periods (N) for the underlying EMA evaluation. Must be greater than 0. Default is 13.

Historical quotes requirements

You must have at least 2×N or N+100 periods of quotes, whichever is more, to cover the convergence periods. Since this uses a smoothing technique, we recommend you use at least N+250 data points prior to the intended usage date for better precision.

quotes is a collection of generic TQuote historical price quotes. It should have a consistent frequency (day, hour, minute, etc). See the Guide for more information.



Convergence warning: The first N+100 periods will have decreasing magnitude, convergence-related precision errors that can be as high as ~5% deviation in indicator values for earlier periods.


Date DateTime - Date from evaluated TQuote

Ema double - Exponential moving average

BullPower double - Bull Power

BearPower double - Bear Power


See Utilities and helpers for more information.


Results can be further processed on (BullPower+BearPower) with additional chain-enabled indicators.

// example
var results = quotes

This indicator must be generated from quotes and cannot be generated from results of another chain-enabled indicator or method.