Purpose of the Bill Williams MFI
The Bill Williams Market Facilitation Index (BW MFI) measures how efficiently price moves. It is the candle's range (high minus low) divided by its volume. A rising value means price moves more easily; a falling value means the market needs more volume to move.
How It Works
The Bill Williams MFI has no period settings. It is calculated with tick volume, MetaTrader's standard for this indicator.
When you select Bill Williams MFI in the Trade Rule block, you can configure it with the following settings:
Time Frame of BW MFI
Sets the chart time frame for the BW MFI calculation.
Can be replaced with a variable or input for quick testing and optimization.
Candle ID of BW MFI
Defines which candle the calculation starts from.
0: Current candle (still forming).
1: Most recently closed candle.
Higher IDs refer to older candles.
Adjust of BW MFI (Modify the Result)
Apply an adjustment to the calculated value by adding, subtracting, multiplying, or dividing by a number.
Example
If you set:
Candle ID: 1
You get the BW MFI value of the most recently closed candle. Compare it with the previous candle's value to see whether price is moving more or less easily.
Use Cases
Detect easier price movement when the BW MFI rises compared with earlier candles.
Combine with volume to judge whether a move has real participation.
Use as a filter to avoid trading in sluggish market conditions.
⚠ Tip: BW MFI values are very small and differ per symbol. Compare them with earlier candles rather than with a fixed number.