Money Flow Index¶

Definition¶

The Money Flow Index (MFI) indicator is a momentum oscillator that calculates buying and selling pressure using both price and volume analysis. It oscillates between 0 and 100; a rising MFI reflects stronger buying pressure, while a falling MFI points to increasing selling pressure. The MFI indicator is typically used to identify trend reversals and price extremes.

MobileDesktop

History¶

The Money Flow Index was created in the late 1980s by Gene Quong and Avrum Soudack, both experienced technical analysts. They designed the MFI to improve upon traditional momentum indicators by incorporating volume data into price analysis, offering traders a more comprehensive view of market strength compared to the widely used Relative Strength Index (RSI).

Calculations¶

In most cases, the MFI value is calculated using the following steps:

1. The Typical Price is calculated as the average of the high, low and closing prices for each period.

\[ Typical\ Price = { {High + Low + Close} \over 3 } \]

2. The Raw Money Flow is calculated by multiplying the Typical Price by the volume for a given period.

\[ Raw\ Money\ Flow = { Typical\ Price \times Volume } \]

3. The Money Flow Ratio (MFR) is calculated as the ratio of the Positive Money Flow to the Negative Money Flow.

\[ MFR = { {Positive\ Money\ Flow} \over {Negative\ Money\ Flow} } \]

    \(Positive\) \(Money\) \(Flow\) – the sum of the Raw Money Flow on the days when the Typical Price is higher than the previous day

    \(Negative\) \(Money\) \(Flow\) – the sum of the Raw Money Flow on the days when the Typical Price is lower than the previous day

4. The Money Flow Index is calculated by the following formula:

\[ MFI = { 100 - {100 \over {1 + MFR} } } \]

Interpretation¶

The MFI indicator is calculated using 14 periods by default, but other periods can be adjusted based on the strategy.

The main patterns of the indicator behaviour can be interpreted as follows:

• Crossovers – the MFI values range between 0 and 100. Readings above 80 are typically considered overbought, suggesting a potential price correction, such as a downward pullback or a consolidation phase. Conversely, values below 20 are seen as oversold, signalling possible upward price momentum.

• Divergence – when the MFI indicator moves in the opposite direction to the symbol price, this can signal potential reversals. For instance, if prices rise while the MFI falls, it may indicate weakening buying pressure. The opposite behaviour, when the price makes a new high but the MFI shows a lower high, suggests diminishing strength in the upward trend, potentially forecasting a price decline.

• Failure swings – failure swings can signal potential price reversals, functioning independently of price changes and focusing solely on the MFI. They can indicate either a bullish or bearish trend according to the swing direction. A bullish trend occurs when the MFI drops below 20 and then rebounds above it, maintaining strength. Conversely, a bearish trend happens when the MFI rises above 80, drops back and then dips below its previous low.

• Shift – by adjusting the shift parameter to alter the alignment of the MFI indicator with price data on the chart, you can explore how the MFI readings correspond to past or future price movements.

Application¶

• Buy signal – traders can consider entering a buy position when the MFI value drops below 20, indicating oversold conditions, then rebounds above it, suggesting increased buying pressure.

• Sell signal – traders can consider entering a sell position when the MFI value rises above 80, indicating overbought conditions, and then falls below this level, indicating potential selling pressure.

• Stop-loss placement – it is recommended to set a stop loss slightly below the recent swing low for buy signals and above the recent swing high for sell signals.

• Confirming trades – to confirm the MFI signals, traders frequently utilise additional indicators like price action and trend analysis, as described above, to enhance their decision-making process.

Limitations¶

The Money Flow Index has several limitations, including its reliance on historical data, which can delay signals. It may produce false positives in choppy markets and is less effective during extreme market conditions. Additionally, the MFI can lag price movements, leading to missed opportunities. Traders should combine the MFI with other indicators for more robust analysis and risk management.

Summary¶

The Money Flow Index is a momentum indicator that measures the buying and selling pressure based on price and volume over a specific period, typically 14 days. It ranges from 0 to 100, with values above 80 indicating overbought conditions and those below 20 signalling oversold conditions. Traders utilise the MFI to identify potential reversals and market strength, helping them make informed trading decisions.