POC

What it is

POC stands for Point of Control: the single price level inside a volume profile window where the most volume traded. If you look at a session's volume profile as a horizontal histogram, the POC is the price corresponding to the longest bar. It is the visual peak of the profile.

POC is a derived statistic, not a raw data point. To find it, you build the profile (aggregate per-tick volume by price level over the window), then scan all the buckets and pick the one with the highest total. The window can be a single session, a multi-day swing, the overnight session, an event-based range, any time slice you want to profile.

A profile has exactly one POC by definition (ties are broken by convention, usually the price closest to the session midpoint wins). When the window updates with new ticks, the POC can shift in real time: as volume accumulates at higher or lower prices, the peak moves.

Why it matters

The POC is treated by many traders as the fairest price of the window: the price where the most participants agreed to transact. That gives it gravitational properties: price tends to return to the POC during the session, and prior-session POCs often act as support, resistance, or magnet levels in later sessions.

Three common operational uses:

• Mean-reversion target: if price has rotated away from the POC, a return to the POC is a frequent intra-session target.
• Support / resistance: the POC of yesterday's session often acts as a defended level when price approaches it today.
• Naked POC: a POC from a prior session that has not been revisited becomes a tracked level for future sessions. Markets have a tendency to fill these eventually.

The POC is also a structural diagnostic. A POC near the high of the session's range suggests acceptance up high (likely continuation); a POC near the low suggests acceptance down low (likely continuation in the other direction); a POC in the middle suggests balance.

How it appears on Sierra Chart

Sierra Chart's volume profile studies compute and display the POC natively as a horizontal line at the peak-volume price, color-configurable and extensible to the right edge of the chart. The platform also supports tracking developing POC (the POC of the in-progress session as it forms tick by tick) alongside the final POC of completed sessions.

For ACSIL developers, profile data is computed on top of VAP arrays, so a custom study can derive its own POC by walking the per-price volume cells and picking the maximum.

Common patterns / pitfalls

• POC shifts during the session: a developing POC is not the final POC. Don't anchor decisions to a developing POC as if it were stable.
• Composite profiles can have multi-modal shapes: a long-window profile (e.g., a week) can have two near-equal peaks, in which case the POC is technically the higher of the two but the secondary peak matters operationally.
• Bucket size matters: a finer profile resolution can split what would otherwise be a single POC into two adjacent buckets. Use the same bucket size when comparing profiles across sessions.
• POC vs VWAP: they are different statistics. VWAP is the volume-weighted average price (a mean); POC is the modal price (a mode). They can be far apart in trending sessions.

Related SCS studies

SCS does not currently ship a dedicated POC tracker. Sierra Chart's built-in volume profile study handles the rendering. The Single Print and Gap study identifies the structural opposites of the POC (low-volume, untested levels) inside the same profile-aware analytical frame.