CVD

What it is

CVD stands for Cumulative Volume Delta — the running sum of per-bar delta over a chosen window, most often a session. Where bar delta tells you who was in control during a single period, CVD tells you who has been in control since the window opened.

The math is simple. Start the window at zero. For each new bar, add that bar's delta (buyer-initiated volume minus seller-initiated volume). The resulting curve is CVD. A rising CVD means net buying pressure has accumulated; a falling CVD means net selling pressure has accumulated; a flat CVD means the two sides have balanced out across the period.

Because it is cumulative, CVD smooths out the noise of single-bar delta swings and exposes the underlying net flow trend. It's the order flow equivalent of looking at total inventory change instead of per-minute deliveries.

Why it matters

CVD's main use is to compare flow to price. If price and CVD rise together, the move is supported by net aggressive buying — the trend has participation. If price rises but CVD goes flat or declines, the move is happening without aggressive buying — likely short covering, thin liquidity, or absorption that hasn't broken yet.

Practical reads:

• CVD divergence at session extremes is one of the strongest order flow reversal signals.
• CVD trending in one direction during a price range often precedes the breakout in that same direction.
• A CVD that resets at session open lets you compare today's flow profile against the same time on prior sessions.

How traders use it on Sierra Chart

Sierra Chart computes CVD from the same bid/ask volume data that feeds bar delta. It's typically rendered as a continuous line or filled area in a sub-pane below price, anchored to a session start (RTH open, ETH open, or a custom time). Some traders also plot a separate ETH-anchored CVD to monitor overnight positioning before the cash open.

Most setups pair CVD with price structure: when CVD prints a lower high while price prints a higher high, the divergence is read against the level price is testing. CVD that simply diverges in the middle of a range is much less actionable than the same divergence at a prior POC or session high.

Common patterns / pitfalls

• CVD anchored to the wrong session start is misleading. Compare like-for-like — RTH-anchored vs RTH-anchored.
• A flat CVD during a price move means somebody non-aggressive is doing the work. That's interesting, but it's an observation, not a trade signal.
• CVD divergence without a structural level is usually noise.
• CVD on illiquid contracts or off-hours sessions is statistically thin — don't over-read it.
• Different platforms classify trades slightly differently at the moment of execution, so CVD shapes can vary subtly between feeds.

Related SCS studies

CVD Filled Area renders cumulative volume delta as a filled, session-anchored curve directly under price — the visual default most traders want when reading CVD against levels and divergences.