Bollinger Bands — Volatility ka Visual Map

John Bollinger ne 1980s mein yeh indicator develop kiya. Teen lines se bane hain: Middle Band jo 20-period SMA hai. Upper Band jo Middle Band plus 2 standard deviations hai. Lower Band jo Middle Band minus 2 standard deviations hai.

Standard deviation rolling calculate hoti hai same 20-period ke liye. Jab market volatile hoti hai, standard deviation bada hota hai aur bands wider ho jaate hain. Jab market quiet hoti hai, standard deviation chota hota hai aur bands tight ho jaate hain. Yahi inka key feature hai.

Statistically agar returns normally distributed hote toh approximately 95 percent price actions upper aur lower band ke beech hoti. Lekin real markets mein yeh percentage alag ho sakta hai especially during extreme events.

Band Squeeze tab hota hai jab bands unusually narrow ho jaate hain. Yeh indicate karta hai ki volatility historically low levels pe hai. Volatility mean reverting hoti hai. Low volatility periods high volatility periods se follow hote hain.

Band Squeeze ek warning signal hai ki koi bada move aane wala hai. Direction pata nahi hota lekin magnitude significant hogi. Jab squeeze ke baad price upper band ke bahar nikle toh bullish breakout, lower band ke bahar nikle toh bearish breakdown.

India mein pre-budget ya pre-RBI policy announcement periods mein often Bollinger Band Squeeze observe hota hai. Market uncertainty mein volume aur volatility dono kam ho jaate hain. Event ke baad bada move hota hai.

Percent B (percent b) batata hai ki price bands ke beech relative kahan hai. Formula: percent b = (Price minus Lower Band) divided by (Upper Band minus Lower Band). Value 1 matlab price upper band pe, value 0 matlab price lower band pe, value 0.5 matlab middle band pe.

Bandwidth = (Upper Band minus Lower Band) divided by Middle Band. Yeh normalize karta hai band width ko aur compare karne deta hai different time periods aur securities ko. Low bandwidth squeeze indicate karta hai, high bandwidth expansion.

Dono indicators ek saath use karne se richer picture milti hai. Agar percent b upper extreme pe hai aur bandwidth high hai (expansion phase mein), yeh strong trend continuation suggest karta hai. Agar percent b extreme pe hai lekin bandwidth low hai (squeeze), reversal possible hai.