Developed by J. Wells Wilder, the Parabolic SAR is used to determine the best times
to exit or enter a market and is based on the Stop and Reverse (SAR) method. It
is calculated using both time and price. This results in a series of trailing stops
that look like a parabola when charted.
An intersection of the price with the parabola is taken as a signal to reverse the
current trading position (that is, go from long to short). The indicator is always
in the market - so once a parabola is reached, a new parabola is plotted in the
opposite direction. NOTE: Each stop is displayed on the day in which it is in effect.
The stops are recalculated each day (or for every time period you're using) and
become closer as the trend progresses. Once a trade is initiated, the indicator
allows a few days for a market reaction to the change in trend. As the trend gets
underway, the stop progresses with the market - slowly at first, then in more rapid
increments in the direction the trade was initiated. The stop may sometimes stand
still as the trend consolidates. If the trend fails to continue, the moving stop
will reverse the position and a new time period begins.
This indicator is also referred to as the Parabolic Indicator, Parabolic System
or SAR.