Smoothed standard deviation changing rate. Interpretation of the indicator values:

• High positive values (yellow) indicate an increasing trend;
• High negative values (gray) indicate that the trend is falling;
• Zero values after positive ones indicate that the trend continues;
• Zero values after negative ones allow you to assume that the market is flat.

The indicator uses the SmoothAlgorithms.mqh library classes (copy it to <terminal_data_folder>\MQL5\Include). The classes were described in detail in the Averaging Price Series for Intermediate Calculations Without Using Additional Buffers article.

Fig.1. Indicator XStdDevSpeed