The Parabolic SAR (Stop and Reverse) is a popular technical analysis indicator developed by J. Welles Wilder Jr. It is used to determine the direction of an asset's momentum and identify potential reversal points in price trends.
Key Features of Parabolic SAR:
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Trend-Following Tool – Helps traders identify the prevailing trend (upward or downward).
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Reversal Signals – The "SAR" dots switch sides when a trend reversal is likely.
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Stop-Loss Guidance – Often used to set trailing stop-loss levels to lock in profits.
How It Works:
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In an uptrend, the SAR dots appear below the price, acting as support.
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In a downtrend, the dots appear above the price, acting as resistance.
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When the price crosses the SAR dots, a potential trend reversal is signaled.
Formula:
The Parabolic SAR is calculated using an accelerating factor (AF) that increases as the trend extends:
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SARₙ₊₁ = SARₙ + AF × (EP – SARₙ)
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SARₙ = Current SAR value
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AF = Acceleration Factor (typically starts at 0.02, increases by 0.02 each time a new extreme is reached, maxing out at 0.20)
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EP = Extreme Point (highest high in an uptrend, lowest low in a downtrend)
How Traders Use It:
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Trend Confirmation: If SAR is below price, the trend is up; if above, the trend is down.
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Exit Strategy: When SAR flips to the other side, it may signal an exit or reversal.
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Stop-Loss Management: Used as a dynamic trailing stop.
Example:
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If a stock is rising, SAR dots stay below the price. If the price falls below SAR, it may indicate a sell signal.
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Conversely, in a downtrend, if the price rises above SAR, it may signal a buy.
Pros & Cons:
✔ Simple & visual for trend identification.
✔ Works well in strong trending markets.
✖ Whipsaws in sideways (ranging) markets.
✖ Lagging indicator (reacts to price changes rather than predicting them).
Parabolic SAR is commonly used alongside other indicators like Moving Averages or MACD for better confirmation. Would you like an example chart analysis?
