The Money Flow Index is a momentum indicator that combines price and volume data.

The Money Flow Index is also known as volume-weighted RSI. 

The MFI indicator measures the inflow and outflow of money into an asset over a specific period of time (typically 14 days), and is an indicator of "trading pressure." 

A reading over 80 indicates that a security is overbought, while a reading below 20 indicates that the security is oversold.