WB Trading Labs

WB Trading Labs An independent research lab measuring what moves US stocks.

I test popular claims against the data and publish the misses too.

Wojciech Bernacki · independent research, in English and Polish
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Research

Latest studies

Every claim tested so far, in one list →

Study · Can't tell yet

Does selling options before earnings pay? The spread took the gain

−0.50%

of the stock price: the seller's average result at real prices, across 416 US earnings reports

Blue: at real prices. Grey: at the halfway price. Thin lines: margin of error.Average result as a share of the stock price: at real prices −0.50% (margin of error −1.10% to +0.10%), at the halfway price +0.54% (+0.02% to +1.06%).

Study · Does not hold

Does buying options before earnings pay? A call lost 42.8% on average

17%

of the 459 calls bought before US earnings reports made money, at real prices

One square per call. Blue: the 17% that made money. Grey: the rest, which lost money or broke even.459 squares, one per call: 17% made money; 34% found no buyer at the close after the report, a total loss.

Study · Lagged on average, not the typical stock

After their own all-time high, small US stocks lagged on average

+6.8%

small US stocks on average in the year after their own all-time high; after any day, +10.9%. The median small stock: no gap

Blue: the year after an all-time high. Grey: the year after any day. Large, small and micro stocks, left to right.Average change in the year after a stock's own all-time high against the year after any day: large stocks +11.4% against +12.0%, small +6.8% against +10.9%, micro −2.0% against +6.0%.

Study · Same as any day, except small caps

After an all-time high, the S&P 500's next year looked like any other

+11.7%

the S&P 500 on average a year after an all-time high, since 1988; after any day, +10.3%

Blue: a year after an all-time high. Grey: a year after any day. S&P 500, Nasdaq-100, Russell 1000, Russell 2000.Average 12-month change after an all-time high against after any day: S&P 500 +11.7% against +10.3%, Nasdaq-100 +22.3% against +17.9%, Russell 1000 +11.9% against +10.5%, Russell 2000 +2.8% against +9.7%.

Study · Unlike 2000, yields are rising

The 30-year Treasury yield is near 6%, as in 2000, but now rising

4 of 5

past returns of the 30-year yield to 6% came with yields falling; today they're rising

Blue: the 30-year Treasury yield, weekly since 1990. Grey dashed line: 6%. Rings: the five past returns to 6%.The 30-year Treasury yield since 1990 with a line at 6%: five returns to 6% from 1993 to 2000, 4 of them with yields falling; today the yield is rising.

Study · No lasting edge

Analyst upgrades move stocks on the day, then stop

+1.7%

an upgraded stock against the market on the day of the note, across 295,000 rating changes since 2012; then no further move for 45 sessions

Blue: the average upgraded stock against the market, 10 sessions before to 45 after the note. Grey: no difference.Average return against the market after an analyst upgrade: +1.7% on the day of the note, +1.5% 45 sessions later.
Every study and every claim tested so far →

Check it yourselfRun the numbers on your own terms: the S&P 500 after an all-time high and the S&P 500 after a new high in the 10-year Treasury yield.

Market readings

Today's markets against their own history

    Data: FRED, multpl.com (including Robert Shiller's CAPE), Yahoo Finance. Each reading carries its own date, as some series are published days or a month later; on US market holidays they don't change. The shaded band in each chart is the middle half of that reading's history. pp: percentage points. Baa: Moody's lowest investment-grade rating.

    Method

    Compared to what?

    A setup that "works 62% of the time" is worth four points if the market goes up 58% of the time without it. Every claim here is measured against what happens anyway: the market, a typical company, a random day.

    A study sees only the data that existed on the day it is about, and then it is checked on years and companies it has not seen. I run every study in my own research pipeline, which uses AI. I check every number before it is published.

    Wojciech Bernacki

    Wojciech Bernacki

    Engineer, more than 20 years in financial services, investing in US stocks since 2019.

    WB Trading Labs is my independent project: nothing here is for sale, and the views are my own. I invest my own money, and some companies I write about may be ones I hold; the posts stay descriptive either way.

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