Envelopes

ایده به زبان ساده

Prices tend to swing around their average and rarely stray very far from it. Envelopes draw a fence at a fixed distance, say 0.1% for a calm currency pair or 2–3% for a stock, so you can see when a move has gone unusually far.

روش محاسبه

Take a moving average and add or subtract a fixed percentage of it.

Upper = MA × (1 + deviation ÷ 100)
Lower = MA × (1 − deviation ÷ 100)
Defaults: 14-period SMA, deviation 0.1%

نحوه استفاده

• Set the percentage so that most candles stay inside the envelope on your timeframe.
• In ranges, touches of the bands can mark turning points.
• In trends, closes outside the band in the trend direction show strength.

نتیجه‌گیری

• Unlike Bollinger Bands, envelopes do not widen in volatile times, so they are easier to read but adapt less.

مراقب این‌ها باشید

• The right percentage depends on the market and timeframe: adjust it rather than using the default everywhere.

کمی تاریخچه

Percentage bands around a moving average are one of the oldest band techniques, used long before volatility-based bands such as Bollinger's.