Oct 13 close Sign in

Breakouts & channels · daily rule · Healthcare

P&F Double Top on Intuitive Surgical

What the play says

In since Aug 10, 2026at $393.38ISRG since then +7.3%

Next move

Stays in unless a daily close lands below $344.39.

$344.39
−18.4% from the Oct 13 close of $422.06

Next check: the Oct 14, 2026 close

See every reason, for and against, in the Theory tester

ISRG with the play, last two years

ISRGDouble-top buy levelDouble-bottom sell levelPlay inPlay out

Shading shows the play's call from the close that triggered it.

Growth of $10,000 since 2005

P&F Double TopBuy & hold

Log scale. After trading costs, with T-bill interest while out.

The record

The play against buying and holding ISRG over exactly the same dates, after costs.

Play, since 2005Hold, since 2005Play, 5 yrsHold, 5 yrs
Annual return+13.5%+23.6%+8.1%+5.3%
Total return+1,476%+9,968%+47%+29%
Worst drawdown−65.1%−75.9%−35.9%−49.9%
Volatility31.3%39.8%25.1%34.6%
Sharpe ratio0.500.680.280.21
Time invested72%100%
Switches per year4.80

Every call, graded

Right on 38 of 104 closed calls (37%). In calls averaged +7.9%; out calls saw ISRG move +4.5% on average.

CalledCallPriceUntilISRG movedResult
Aug 10, 2026IN$393.38now+7.3%open
Jul 14, 2026OUT$379.50Aug 10, 2026+3.7%✕ wrong
Jul 6, 2026IN$432.83Jul 14, 2026−12.3%✕ wrong
Jan 14, 2026OUT$546.76Jul 6, 2026−20.8%✓ right
Oct 22, 2025IN$527.03Jan 14, 2026+3.7%✓ right
Jul 23, 2025OUT$501.95Oct 22, 2025+5.0%✕ wrong
Apr 23, 2025IN$487.93Jul 23, 2025+2.9%✓ right
Apr 21, 2025OUT$468.32Apr 23, 2025+4.2%✕ wrong
Apr 9, 2025IN$522.95Apr 21, 2025−10.4%✕ wrong
Mar 4, 2025OUT$557.96Apr 9, 2025−6.3%✓ right
Nov 13, 2023IN$282.48Mar 4, 2025+97.5%✓ right
Oct 12, 2023OUT$266.12Nov 13, 2023+6.1%✕ wrong

An in call is right when the price rose before the next call; an out call is right when it fell. The latest 12 of 105 calls shown.

How the play works

  1. In on a double-top breakout: the current X column rises at least one box above the top of the previous X column.
  2. Out on a double-bottom breakdown: the current O column falls at least one box below the bottom of the previous O column.
  3. Otherwise the rule keeps the chart's last signal.

Boxes are 2% apart, and a new column needs a 3-box reversal (about 6%). Dorsey's classic box table uses fixed price bands; ChartSchool's examples use 1% boxes.

The chart is built from daily highs and lows by StockCharts' high-low method: a new box from the high wins, and the low only counts if it reverses the column.

The signal fires on the day the breakout box fills during the day. Be The Puck acts on that day's close.

Where the rules come from

The case against

Valeriy Zakamulin tested moving-average timing on up to 155 years of U.S. stock data and found no statistically significant edge in the second half of that record. The rules earned their keep in a few severe bear markets and lagged buy and hold for long stretches in between.

Read the skeptic's scoreboard

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