BTC Price (USD) is the daily Bitcoin reference price series used across CoreCharts for USD-denominated valuation work. This view adds a compact technical layer on top of price: SMA 50 and SMA 200 for trend context, Bollinger Bands (20,2) for dispersion around the 20-day mean, plus optional overlays that quantify volatility and distance from the long-term mean.

What is computed

SMA 50 and SMA 200 are strict simple moving averages over 50 and 200 daily closes.

Bollinger Bands (20,2) are computed over a 20-day window: Mid = SMA20, Upper = Mid + 2·σ20, Lower = Mid − 2·σ20, where σ20 is the sample standard deviation of price over the same 20-day window.

BB Width % expresses band width as a percentage of the midline: BB Width % = (Upper − Lower) / |Mid| · 100.

Dev vs SMA200 % measures distance from the 200-day mean: Dev % = (Price / SMA200 − 1) · 100.

Z vs SMA200 expresses the distance from SMA200 in standard-deviation units using a 365-day rolling price standard deviation: Z = (Price − SMA200) / σ365(Price).

All rolling values require a full window of valid daily samples before they appear.

How to use it

Treat SMA200 as the primary regime divider and SMA50 as the faster trend reference. In sustained uptrends, price tends to hold above SMA200 with pullbacks that often respect SMA50. In sustained downtrends, rallies frequently stall below SMA200 and SMA50 typically rolls over earlier.

Bollinger Bands provide a practical dispersion envelope. Repeated closes near the upper band reflect persistent demand pressure; repeated closes near the lower band reflect persistent supply pressure.

The overlays are designed for focus: enable only one of BB Width %, Dev vs SMA200 %, or Z vs SMA200 at a time to keep the left axis readable.

Using it for market timing

BB Width % is a direct read on realized dispersion over the last 20 days. Low width signals compression that often precedes expansion. High width signals an active volatility regime, where continuation or exhaustion is best judged by price location relative to SMA50 and SMA200.

Dev vs SMA200 % answers one question in percent terms: how stretched is price from the long-term mean. Large positive deviations often align with late-cycle momentum and help with risk sizing or profit-taking rules. Large negative deviations highlight deep drawdown regimes.

Z vs SMA200 answers a similar question in standardized units: how unusual is the current distance from the long-term mean. This is useful when comparing extremes across very different price levels, because the scale is anchored to 365-day price variability.

Historical context

The 200-day moving average is a long-standing market convention in macro and crypto for defining structural trend regimes. Bollinger Bands were introduced by John Bollinger in the 1980s and are widely used to describe volatility expansion and contraction. BB Width is a standard derivative of Bollinger Bands designed to quantify compression and expansion regimes rather than only visual band placement.