Skip to main content
Track Rounded bottom
6 / 14
Library

2003issue C051-6

Constructing rounded bottoms, triangles, and pennants

A rounded bottom, a triangle pattern, and a pennant are finished only after scale, boundary touches, a duration-gate, and a confirmation-close are in place. TradersWeek editorial: use those construction checks to accept or reject the drawing before writing a trade hypothesis.

  • A rounded bottom is a gradual saucer or bowl after an advance, commonly read on the weekly scale, and construction is complete only after a close above the left bowl-lip high.
  • Volume can trace a bowl with the price saucer, and a declining volume line belongs in the same construction profile as a falling wedge until the boundary break.
  • A contracting look-alike shorter than three weeks is constructed as a pennant; a falling wedge should last at least three weeks, rarely more than four months, and is unfinished with fewer than five boundary touches.
  • An expanding triangle variant uses a horizontal upper line and a descending lower line; a partial decline is read only after both lines already have two touches.
Entries in this reading3 entries

Construction checklists

TradersWeek editorial: treat these uncommon bullish shapes as construction checklists. Chart scale, boundary touches, a duration-gate, and a confirmation-close let a rounded bottom, a contracting or expanding triangle, or a short pennant be accepted or rejected before any trade hypothesis is written.

The historical workflow is a drawing test. A rounded bottom, a triangle pattern, and a flag and pennant are finished only when those construction cues are present.

Rounded bottom

A rounded bottom is constructed as a gradual saucer or bowl after an advance. The weekly scale is commonly used because the arc is large, though that scale is not required.

Construction of a rounded bottom is complete only after a close above the left bowl-lip high. The bowl-lip is the left-side high that a rounding bottom must close above before construction is complete. If a later handle draws a downsloping line, the next construction cue is an upward pierce of that handle line.

Volume during a rounded bottom can itself trace a bowl, so the volume arc belongs in the same construction reading as the price saucer.

A large ascending triangle can occupy the approach to a rounding bottom, so a flat-top triangle is a valid lead-in geometry rather than only a rising trend into the bowl.

Rounded bottom after the mid-1999 selloff

Read from the daily OHLC raster, price slides from the mid-15s into a late-September print near 10, then spends October through February rounding in a 10–12 band before the March–April close-up through 13–14 finishes the saucer. That multi-month base and the close above the rim are the construction checks a trader can accept or reject.
Read from the daily OHLC raster, price slides from the mid-15s into a late-September print near 10, then spends October through February rounding in a 10–12 band before the March–April close-up through 13–14 finishes the saucer. That multi-month base and the close above the rim are the construction checks a trader can accept or reject.Daily · 1999-04-01T00:00:00.000Z to 2000-04-30T00:00:00.000Z

Weekly representative closes lifted from the daily bars. The print supports about 0.1 price resolution and publishes no numeric table.

Falling wedge, pennant, and the duration-gate

A falling wedge is constructed from two downward-sloping boundaries that join at an apex, each with at least two minor-high and two minor-low touches, frequent crossings, and little empty space inside the lines.

A contracting look-alike shorter than three weeks is constructed as a pennant rather than a falling wedge. A falling wedge should last at least three weeks and rarely more than four months. That span is the duration-gate that separates a falling wedge from a pennant.

Treat a falling-wedge drawing as unfinished when it has fewer than five boundary touches, typically two on one line and three on the other.

Along a falling wedge, volume typically recedes until the boundary break, so a declining volume line is part of the construction profile.

Expanding triangle and the partial decline

An expanding triangle variant is constructed with a horizontal upper line and a descending lower line so the range widens over time.

A partial decline is a pullback from the upper boundary that turns up before reaching the lower boundary. A partial decline is read only after both lines already have two touches.

Educational research material, not investment advice. Historical source context does not establish present-day performance.
6 of 14 in the Rounded bottom track
20061-6 pp.Next on Rounded bottomA five-by-five grid that accepts or rejects a cupA rounded bottom, also called a cup, can be stated as occupancy rules on a five-by-five log-price and time grid.
All readings on this track · 14 readings
  1. 1990Constructing falsifiable reversal patterns from price structure
  2. 1995Cup-with-handle construction: confirm the cup, the handle, then the breakout
  3. 1995Cup-completion cheat before the handle breakout
  4. 1998Constructing rounded-bottom cups as testable entries
  5. 1999Rounded bottom landmarks, invalidation, and breakout rules
  6. 2003Constructing rounded bottoms, triangles, and pennants
  7. 2006A five-by-five grid that accepts or rejects a cup
  8. 2006NTRI and the 2005 bowl breakout case
  9. 2006Rounded-bottom screens, first-try breakouts, and Fibonacci retracements
  10. 2007Constructing rounded bottoms as multi-year bases
  11. 2011Early semi-cup construction from the left rim and base
  12. 2011Early rounded bottom recognition on a locked log-price grid
  13. 2013Rounded turns as slope-first trade hypotheses
  14. 2017Evaluating a rounded bottom as a testable payoff structure
All 14 readings tagged Rounded bottom
Also on Rounded bottom5 readings