What it means
On a daily high-low chart, an upward gap occurs when the current day's low is above the previous day's high, and a downward gap occurs when the current day's high is below the previous day's low. This creates an interval between the two bars with no overlapping traded range.
A close-to-open jump is a related observation but not identical, because prices can open far from the previous close and later overlap the earlier day's range, so analysts should specify their gap definition rather than combine measurements in one performance claim. The runaway label adds context, since technical analysts use it for a gap during a trend rather than simply any gap up or down.
The proposed interpretation is that the existing direction has gained momentum, not that the gap has created an independently guaranteed return. The usual contrast is with breakaway and exhaustion gaps: a breakaway gap is associated with leaving a formation or range, while an exhaustion gap is associated with a late surge that may precede reversal.
These are classifications of context and subsequent behaviour, not different physical objects visible with certainty at the instant of the jump. Academic authors Dahlquist and Bauer discuss these categories in their 2011 study of gaps, and they emphasise that classifications which seem clear in hindsight can look similar as they occur.
Their research uses a defined historical stock sample and should not be read as a promise about a current asset. Some charting accounts propose that a measuring gap occurs partway through a move and can help project a target.
That is a heuristic, not a contract with the market, and the origin of the trend and the distance already travelled can be ambiguous, making the projection sensitive to the analyst's choices. No universal percentage jump makes every gap a runaway gap, so size should be evaluated alongside the asset's normal movement, interval and chart definition, because an arbitrary threshold can change which observations enter a backtest.
A gap can create execution risk, as a stop trigger might be passed between available prices, leaving an order executed at a different level than intended. A manager reviewing a trading plan should distinguish its intended loss limit from a guaranteed sale price.
For a non-finance manager, the useful question is what the chart description adds to a decision, so ask for a reproducible definition, the supporting evidence and the loss scenario. The label should organise an observation rather than substitute for a risk-controlled investment process.
Treat it as a hypothesis to test against costs and downside, not as a forecast.
In practice
Real-world examples.
Example
A fictional share's previous high is 50, and the following day's low is 52. The daily bars have an upward gap of 2 price units. Calling it runaway still requires a stated trend context; the arithmetic alone does not predict another rise.
Example
A share opens above yesterday's close but falls back into yesterday's range. It has an opening jump but not the full high-low gap used in a particular study. Applying that study's findings without matching its definition is misleading.
Example
A trader calls a gap continuation before a later decline. Afterward, another analyst labels it exhaustion. The change illustrates the danger of judging a real-time decision using a classification available only with hindsight.
Formula
Calculation
Illustrative upward high-low gap = current low - previous high, when the current low exceeds the previous high. With 52 and 50, the gap is 2; relative to the previous high, it is 2 / 50 x 100 = 4%.
This measures the chart interval. It does not prove the gap is a continuation pattern or establish a universal 4% threshold. The downward definition reverses the relevant high-low comparison.Case study
Seen in the real world.
Fictional case study: Vale Investments receives a proposal to buy after a supposed runaway gap. Its review team asks how the analyst defines the trend and separates an opening jump from a full-range gap. The analyst records a testable entry rule, invalidation condition and costs.
The team also checks what happens if price jumps past the planned exit. It treats the idea as an uncertain market hypothesis. A later chart annotation is not accepted as evidence that the original trade was guaranteed to work.
Watch out
Common mistakes.
- Calling every opening jump a full chart gap without checking the high-low ranges.
- Reclassifying losing signals with hindsight and excluding them from a performance test.
- Treating a measuring-gap target or stop trigger as a guaranteed future execution price.
Questions
People also ask.
Is a runaway gap always bullish?
No. It can occur in a downward trend as well as an upward one.
Must the gap later fill?
No universal rule guarantees that price returns through the gap or specifies when.
Does heavy volume prove continuation?
No. It supplies context, but the interpretation can still fail.
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