--- title: "Forecast Oscillator: Formula, Meaning" description: "Tushar Chande's Forecast Oscillator shows the percentage difference between price and its time series forecast, the value implied by extending a linear..." canonical: https://www.getswoopr.com/indicators/trend/forecast-oscillator/ source: "Swoopr Investment: https://www.getswoopr.com" --- ## Direct Answer > Tushar Chande's Forecast Oscillator shows the percentage difference between price and its time series forecast, the value implied by extending a linear regression line fitted to recent prices. Positive values mean price is above the regression forecast, and negative values mean price is below it. A linear regression assumes a straight-line trend and can be misleading around turns or in curved moves. # Forecast Oscillator: Formula, Meaning, Signals, Examples and How to Use It ## How Is Forecast Oscillator Calculated? Tushar Chande's Forecast Oscillator shows the percentage difference between price and its time series forecast, the value implied by extending a linear regression line fitted to recent prices. **Formula:** `FOSC = 100 * (Close - TSF) / Close, where TSF is the endpoint of the n-period linear regression forecast` **Inputs:** - Closing prices - Regression period n - Time series forecast (TSF) value at the latest bar **Worked example.** A close of 105 against a regression forecast of 103 gives a Forecast Oscillator reading of 1.9%. The inputs are illustrative numbers, not market data. **Reading it.** Positive values mean price is above the regression forecast, and negative values mean price is below it. The reading is expressed as a percentage of price, so it can be compared across instruments. **Limits.** A linear regression assumes a straight-line trend and can be misleading around turns or in curved moves. Results change with the regression window. ## What is Forecast Oscillator? Tushar Chande's Forecast Oscillator shows the percentage difference between price and its time series forecast, the value implied by extending a linear regression line fitted to recent prices. ## How to use Forecast Oscillator Positive values mean price is above the regression forecast, and negative values mean price is below it. The reading is expressed as a percentage of price, so it can be compared across instruments. A reading alone is never a buy or sell signal; it needs context from price structure, volume, volatility and the broader market regime. ## Strengths - Dividing the gap by the close expresses it as a percentage, so it is comparable across instruments and over long price ranges. - Zero is a natural reference line, the point where the close equals the regression forecast, so crossings are well defined. - Reproducible when the formula and data convention are fixed. ## Weaknesses and limitations - The forecast comes from a line that includes the current bar, so the oscillator partly measures distance from a line that price itself has pulled. - In low-priced instruments a small absolute gap is a large share of the close, so the percentage form can look exaggerated. - Correlated indicators can create false confidence by repeating the same underlying information. ## Editorial and risk note This page is educational content, not individualized investment advice. It should not imply guaranteed prediction, accuracy or outperformance. ## Frequently Asked Questions Is Forecast Oscillator a buy or sell signal? No. Positive values mean price is above the regression forecast, and negative values mean price is below it. A linear regression assumes a straight-line trend and can be misleading around turns or in curved moves. A trade built on it still needs a trigger, an invalidation rule, a position size and realistic execution assumptions. What is the best setting for Forecast Oscillator? Forecast Oscillator takes these inputs: closing prices; regression period n; time series forecast (TSF) value at the latest bar. There is no universal best setting for the tunable ones, so test them across instruments, regimes and out-of-sample periods and favor stable parameter regions over one historical winner. Can Forecast Oscillator be used by itself? A linear regression assumes a straight-line trend and can be misleading around turns or in curved moves. Results change with the regression window. For that reason it is read next to measures of direction, participation, valuation, liquidity and risk, not alone. Does Forecast Oscillator work on every timeframe? The calculation (FOSC = 100 * (Close - TSF) / Close, where TSF is the endpoint of the n-period linear regression forecast) can be run on any bar size, but behavior is not portable: a reading on a five-minute chart describes a very different market window from the same reading on a daily chart. Validate the exact timeframe before relying on it. Why does Forecast Oscillator give false signals? The forecast comes from a line that includes the current bar, so the oscillator partly measures distance from a line that price itself has pulled. In low-priced instruments a small absolute gap is a large share of the close, so the percentage form can look exaggerated. Lag, noise and regime changes add to this, because market participants react to new information after the reading is calculated. How should Forecast Oscillator be backtested? Rebuild Forecast Oscillator from closing prices using point-in-time data, write the rules before testing, include delisted securities where relevant, model realistic fills and costs, reserve a validation sample and compare with a simpler baseline. S Swoopr Editorial Team The Swoopr Editorial Team produces independent investment education, research, and tools for understanding markets, evaluating opportunities, and managing risk. All content is educational only and does not constitute personalized investment advice. See our [editorial policy](https://www.getswoopr.com/legal/editorial-policy/) and [corrections policy](https://www.getswoopr.com/legal/corrections-policy/).