Period 16 Review: Piotroski's GLOB-Powered Surge Vaults It from Last to First as Quality Growth's Slide Extends

Period 16 covers July 25 to August 1, 2026 — seven days that broke two separate streaks at once. Five screens closed positive and two negative, the same 5-of-7 split as Period 15, but with a different lineup: Piotroski F-Score and Magic Formula flipped from red to green, while CANSLIM Rocket flipped the other way. The spread between best and worst narrowed sharply to 5.31 percentage points — Piotroski at +2.37% and Quality Growth at −2.94% — breaking the widening trend that had run from Period 12 (6.06 points) through Period 15 (7.63 points). Both benchmarks closed positive for the first time in three periods, the S&P 500 at +1.05% and the NASDAQ at +1.59%, after both had fallen together in Period 14 and Period 15.

The period's headline is Piotroski's reversal: last period's cumulative cellar-dweller jumped to the week's best screen almost entirely on the back of one position. GLOB (Globant), which had slipped −2.89% in Period 15, surged +16.93% this period and single-handedly contributed more than half of Piotroski's total return. Meanwhile Quality Growth, which posted its worst-ever period just one week earlier on SEZL and DAVE, fell again — this time led down by FICO's −9.25%, its steepest single-period drop since joining the screen, with DAVE adding a second straight decline of its own.

Period 16 Returns: Piotroski Leads as Quality Growth Falls Again

Piotroski F-Score topped the table at +2.37%, followed by Magic Formula at +1.66% and Lunch at +1.56%. Schloss Dividend added +0.80% and Burry Value Screen closed at +0.54%, leaving five of seven screens positive. Only CANSLIM Rocket (−1.20%) and Quality Growth (−2.94%) closed in the red, with Quality Growth posting the week's worst result for the second period running.

Piotroski's +2.37% was its best result since joining the journal, driven overwhelmingly by GLOB (Globant), which gained +16.93%, from $31.30 to $36.60, contributing approximately +1.41 percentage points at the screen's 8.33% equal weight — more than half the screen's total return from a single name. YALA (Yalla Group) added +4.05% (+0.34 points), USNA (USANA Health Sciences) rose +3.71% (+0.31 points), and LUXE (Luxshare) and MOMO (Hello Group) each contributed roughly +0.16 points. Against these, NOAH (Noah Holdings) fell −1.40% (−0.12 points) and WGO (Winnebago Industries) declined −1.59% (−0.13 points). Eight of eleven retained positions closed positive. GDYN (Grid Dynamics) exited at the sell fee; IPI (Intrepid Potash) and TRC (Tejon Ranch) enter the screen for Period 17, growing Piotroski from twelve to thirteen names.

Magic Formula's +1.66% extended its Period 15 rebound, led by CGAU (Centerra Gold), which gained +6.18%, from $16.19 to $17.19, contributing approximately +0.51 percentage points at the 8.33% weight. INSW (International Seaways) added +4.23% (+0.35 points), DDS (Dillard's) rose +3.57% (+0.30 points), and FHI (Federated Hermes) gained +3.52% (+0.29 points). Against these, IAG (IAMGOLD) fell −3.21% (−0.27 points), the screen's single largest drag, and BVN (Compañía de Minas Buenaventura) declined −2.04% (−0.17 points). Nine of twelve retained positions closed positive, and all twelve were retained — the screen's second straight period of perfect retention. TNK (Teekay Tankers) enters the screen for Period 17, growing Magic Formula to thirteen names.

GLOB fell −2.89% in Period 15. One week later it surged +16.93% and single-handedly carried Piotroski from last period's −1.24% to this period's best result in the journal — the same kind of single-stock, single-period whiplash that has defined this journal's most extreme screens all year.

Lunch's +1.56% was its third straight positive period, led by ESTC (Elastic), which gained +12.12%, from $58.68 to $65.79, contributing approximately +0.67 percentage points at the 5.56% weight. ATAT (Atour Lifestyle) added +7.45% (+0.41 points), PDD (PDD Holdings) rose +7.14% (+0.40 points), and BZ (Kanzhun) gained +5.58% (+0.31 points). Against these, PLMR (Palomar Holdings) fell −2.74% (−0.15 points) and PAAS (Pan American Silver) declined −2.09% (−0.12 points). Seven of fourteen retained positions closed positive. CPRX (Catalyst Pharmaceuticals), EXE (Expand Energy), PATH (UiPath), and TTD (The Trade Desk) all exited at the sell fee, the screen's largest single-period contraction since Period 12; SKHY (Skyward Specialty Insurance) enters for Period 17, shrinking Lunch from eighteen to fifteen names.

Schloss Dividend's +0.80% was led by ATHM (Autohome), which surged +10.00%, from $21.11 to $23.22, contributing approximately +0.91 percentage points at the 9.09% weight — more than the screen's entire period return on its own. TX (Ternium) added +4.10% (+0.37 points) and GGB (Gerdau) gained +3.12% (+0.28 points). Against these, MTH (Meritage Homes) fell −3.77% (−0.34 points) and LEN (Lennar) declined −2.71% (−0.25 points). Five of eleven positions closed positive. All eleven positions were retained for the second consecutive period — Schloss now shares the journal's longest active perfect-retention streak with Magic Formula.

Burry Value's +0.54% masked a wide spread across its thirty-four positions. NTES (NetEase) led with +11.48%, from $119.55 to $133.27, contributing approximately +0.34 percentage points at the 2.94% weight — a sharp reversal from its −8.94% drop in Period 15. ZM (Zoom Communications) added +9.18% (+0.27 points) and APPF (AppFolio) gained +9.17% (+0.27 points). Against these, WSO (Watsco) fell −14.56% (−0.43 points), the period's single worst position-level drag for any screen, and LRN (Stride) declined −7.59% (−0.22 points). Seventeen of thirty-one retained positions closed positive. AEM (Agnico Eagle), CPRX (Catalyst Pharmaceuticals), and GRBK (Green Brick Partners) all exited at the sell fee; JOE (The St. Joe Company) enters the screen for Period 17, leaving Burry at thirty-two names.

CANSLIM's −1.20% was dragged down by MU (Micron Technology), which fell −10.63%, from $920.95 to $823.03, subtracting approximately −0.53 percentage points at the 5% weight — its second reversal in as many periods, following a +8.48% rebound in Period 15 that itself followed a −13.31% collapse in Period 14. FN (Fabrinet) declined −8.53% (−0.43 points) and DY (Dycom Industries) fell −6.69% (−0.33 points). Against these, CLS (Celestica) gained +8.57% (+0.43 points) and MPWR (Monolithic Power Systems) added +6.91% (+0.35 points). Seven of eighteen retained positions closed positive. GLW (Corning) and SKHY (Skyward Specialty Insurance) exited at the sell fee; APH (Amphenol) and BE (Bloom Energy) enter the screen for Period 17, keeping CANSLIM at twenty names.

Quality Growth's −2.94% was its second straight worst-place finish, dragged down by FICO (Fair Isaac), which fell −9.25%, from $1,237.37 to $1,122.97, subtracting approximately −1.16 percentage points at the screen's 12.5% weight — the single largest position-level drag of any screen this period. DAVE (Dave Inc.) declined a further −7.48% (−0.94 points), from $402.81 to $372.69, its second consecutive negative period after Period 15's −8.54%. NBIX (Neurocrine Biosciences) fell −5.10% (−0.64 points) and AUPH (Aurinia Pharmaceuticals) declined −3.06% (−0.38 points). Only APP (AppLovin, +1.00%) and SEZL (Sezzle, +0.56%) closed positive — the same two stocks that led the screen's collapse in Period 15 now stabilizing, while the previously steady FICO and DAVE became the drags. CNX (CNX Resources) and ELMD (Electromed) exited at the sell fee; ALNY (Alnylam Pharmaceuticals), INCY (Incyte), and RDDT (Reddit) enter for Period 17, growing Quality Growth from eight to nine names.

Retention: Schloss and Magic Formula Both Post a Second Straight Perfect Period

Period 16 handed perfect retention to the same two screens as last time. Schloss Dividend and Magic Formula both held 100% of their starting positions for a second consecutive period, while Quality Growth posted the field's lowest retention at 75.0%, narrowly behind Lunch at 77.8% — the same two screens that turned over the most in Period 15's overlap shifts.

Piotroski jumped the most in rank, from last place at 85.7% to third at 91.7%, while Lunch and Quality Growth both fell from the middle of the pack to the bottom two spots. The overall spread widened noticeably: Period 15's retention figures ranged from 85.7% to 100% (a 14.3-point spread), while Period 16 ranges from 75.0% to 100% (a 25.0-point spread) — the widest retention spread the journal has recorded since Period 5.

Cumulative Scoreboard: Order Holds Steady for the First Time in Months

Quality Growth's second straight loss trimmed its cumulative return from +17.62% to +14.16%, its second-steepest single-period decline of the journal after Period 15 itself, but it remains the only screen with a positive cumulative alpha against both benchmarks. For the first time since at least Period 13, every screen closed Period 16 in the exact same cumulative rank it held after Period 15 — no reshuffling at the top or the bottom.

Schloss Dividend's +0.80% lifted its cumulative return to +8.57% from +7.70%, holding second place comfortably. CANSLIM's −1.20% trimmed its cumulative return to +3.58% from +4.84%, its first cumulative decline in three periods, while still holding third. Burry Value's +0.54% nudged its cumulative return to +1.63% from +1.08%, and Lunch's +1.56% narrowed its cumulative loss to −0.25% from −1.79%, putting it within one strong period of turning cumulatively positive for the first time in the journal. Magic Formula's +1.66% trimmed its cumulative loss to −7.00% from −8.52%, and Piotroski's +2.37% — its best result yet — was still not enough to lift it out of last place, narrowing its cumulative loss to −10.94% from −13.00%.

Against benchmarks, both indices' return to positive territory reversed most of the cumulative alpha gains screens had made in Period 15. Quality Growth's alpha narrowed sharply, from +8.32/+7.58 to +3.72/+2.37 versus the S&P 500 and NASDAQ respectively, as its own loss compounded with both benchmarks' gains. CANSLIM's alpha widened negative the most of any screen, from −4.46/−5.20 to −6.86/−8.21, a swing of more than two points on each side. Lunch moved from −11.09/−11.83 to −10.69/−12.04, Burry from −8.22/−8.96 to −8.81/−10.16, and Schloss from −1.60/−2.34 to −1.87/−3.22 — all worsening versus the NASDAQ specifically, since the NASDAQ's +1.59% gain outpaced every screen's own period return except Piotroski's and Magic Formula's. Only two screens improved: Magic Formula's alpha moved from −17.82/−18.56 to −17.44/−18.79 (better versus the S&P 500, slightly worse versus the NASDAQ), and Piotroski's improved on both counts, from −22.30/−23.04 to −21.38/−22.73, since its +2.37% actually outran both benchmarks outright.

Overlap: Seven Stocks as Lunch Loses AEM and CPRX Dissolves Entirely

The August 1 snapshot shows seven stocks in two or more screens, down from eight on July 25. AEM exited Burry Value Screen, dissolving its pairing with Lunch, while it remains a single-screen holding in Lunch alone. CPRX exited both Burry Value Screen and Lunch on the same day, erasing that overlap entirely rather than just shrinking it — the second time in three periods a shared pair has vanished this way. Taking their place, INCY entered Quality Growth while remaining held in Burry Value Screen, creating a new pairing between the two screens for the first time in the journal.

Lunch still anchors four of the seven overlap pairs — FSM and HRMY shared with Burry Value, PLGO shared with Schloss, BVN shared with Magic Formula, and PAAS shared with CANSLIM. Burry Value and Lunch together now share just two tickers, down from four last period, as AEM and CPRX both dropped out of the overlap in the same week. This period the shared names cut mixed: FSM's −1.40% and HRMY's −0.23% weighed lightly on both Burry and Lunch, PAAS's −2.09% pulled on both Lunch and CANSLIM, while PLGO's −1.13% dragged Schloss and Lunch together. BVN's −2.04% was the one shared name to hurt both of its screens meaningfully, denting Lunch and cutting further into Magic Formula's gain. LUXE, the lone pair not involving Lunch, added +1.88% and lifted both Piotroski and CANSLIM slightly, though CANSLIM's overall result stayed negative regardless.

What Period 16 Tells You

A single stock can flip a screen's fortunes overnight — in either direction. GLOB's −2.89% in Period 15 and +16.93% in Period 16 turned Piotroski from last period's laggard into this period's best screen almost entirely on its own, contributing more than half the screen's total return. It is the same dynamic that sank Piotroski's peers in past periods — HMY and ORLA for Magic Formula, SEZL and DAVE for Quality Growth — now working in the other direction for a screen that had never before posted its best result in the journal.

Mean reversion is not universal — some stocks keep falling. Period 15's review noted that Magic Formula's and CANSLIM's worst names became their best contributors the very next period. MU looked set to repeat that pattern after its Period 14 collapse and Period 15 rebound, but Period 16 sent it down again, −10.63%. DAVE similarly failed to reverse, declining for a second straight period after Period 14's surge. The lesson from Period 15 — that single-period extremes tend to snap back — held for GLOB and NTES this period, but not for MU or DAVE, a reminder that reversal is a tendency in this journal's data, not a rule.

Quality Growth's concentration keeps finding a new weak point. With only six to nine positions, Quality Growth's results have swung hard on one or two names in nearly every period reviewed. FICO's −9.25% alone accounted for essentially the entire screen's −2.94% loss this period, just as SEZL and DAVE had driven its worst period on record one week earlier. The screen keeps rotating which single position does the damage, but the underlying structural exposure to concentration risk hasn't changed — and it remains the only screen beating both benchmarks cumulatively despite two consecutive losing periods.

A positive benchmark period raised the bar, and most screens didn't clear it. After two periods of both benchmarks falling, the S&P 500's +1.05% and NASDAQ's +1.59% this period meant that even screens with solid absolute returns lost ground on a relative basis. Only Piotroski and Magic Formula outran both benchmarks outright; Schloss, Burry, and Lunch all posted gains that still trailed the NASDAQ, and CANSLIM and Quality Growth lost ground on both counts. It's a reminder that "positive screen returns" and "screens beating the market" are different bars, and this period most screens cleared only the first one.