British Airways share prices

Use this diagram to show that low-order running medians can be used to remove the effect of outliers, followed by running means of the resulting series, will give a more 'rounded' smooth series.

Set the checkbox Drag outlier then drag the 30th value to about 160.

Set the run length for the initial running medians to 3, then set the run length for the running means to 3 or 5.

The time series shows the price of British Airways shares in the first 57 trading days of 2002 — between 2nd January and 21st March.