SESSION ATR PERCENT

What it does

Session ATR Percent displays the current session's Average True Range as a percentage of its historical average, shown as a text overlay directly on your chart. It tells you at a glance whether today's session is running hotter or cooler than normal: a single number that captures whether you're in a typical, extended, or compressed range day.

Raw ATR values are hard to interpret without context. "ATR is 12 points" means nothing on its own: is that high for this instrument? Low? About average? Session ATR Percent normalizes the answer: 100% means today matches the historical average, 150% means today is running 50% hotter, 60% means today is unusually compressed. The reading updates throughout the session as the current range builds.

Key features

• Normalized ATR reading: current session range expressed as a percentage of the rolling N-day average, instantly comparable across instruments and across days.
• Live text overlay on the main chart: no separate subgraph or pane, no scrolling between regions.
• Configurable session window: set the start and end times that define "today's session" for your trading style (RTH, full session, or any custom window).
• Adjustable history length: 1 to 500 days of rolling average, so you can compare today's session against the last week, the last month, or the last quarter.
• Persistent rolling history: completed session ATRs are stored and survive chart recalculations, so you don't lose historical context every time you reload.
• Full text styling: color, background color, font size, and X/Y screen position so it fits cleanly on any chart layout.

How it works

After purchase, Session ATR Percent is added to your Sierra Chart account automatically. Restart Sierra Chart, then add the study to a time-based chart (1 minute, 5 minutes, 1 hour, or any time-based bar type) via Analysis → Studies → Add Custom Study → Session ATR Percent. Configure the session start and end times to match the window you care about, set the history length, and position the text overlay.

At runtime, the study computes the ATR for the current session within the configured time window and divides it by the rolling average ATR over the last N completed sessions. The result is displayed as a percentage on the chart. When the session ends, that day's ATR is added to the rolling history and the oldest value drops off if the window is full. The next session starts fresh, and the reading rebuilds from there.

The study requires a time-based chart because it relies on time-based session boundaries to define what "today's session" means. It will not work on tick, volume, range, or Renko charts.

Who it's for

• Day traders who size positions based on session volatility: knowing whether today is a 130% day or a 70% day informs target placement, stop width, and how aggressively to trade.
• Mean-reversion traders who fade extended ranges: a reading above 150% flags days when the historical statistical edge is more relevant.
• Breakout traders who avoid compressed sessions: a reading below 70% signals a day where conventional breakout setups may stall.
• Prop firm traders (Apex, Topstep, MyFundedFutures) managing daily loss limits: the reading helps calibrate position size to the actual volatility of the day.

Compatibility & requirements

• Requires Sierra Chart with ACSIL custom study support
• Must be applied to a time-based chart (1 minute, 5 minutes, etc.); not compatible with tick, volume, range, or Renko bars
• Windows desktop platform
• Compatible with any instrument that has session-defined trading hours
• No external dependencies: runs as a native Sierra Chart custom study
• Automatic activation on your Sierra Chart account after purchase; no DLL download or manual installation required
• Lifetime updates included

Support

• Email support: support@scstudies.com (response within 24 hours on business days)
• Discord community: https://discord.gg/8agxJx6wRN