Period 21 Review: CANSLIM Rocket Tops a Record-Tight Field as Six of Seven Screens Turn Positive

Period 21 covers August 29 to September 5, 2026 — a quiet period at the index level that produced an unusually tight field of screen results. The S&P 500 added a scant +0.09% and the NASDAQ +0.40%, both far calmer than Period 20's +0.49%/+0.85%. Six of the journal's seven screens closed positive, led by CANSLIM Rocket's +2.21% and Magic Formula's +1.38%, while Piotroski F-Score was the only screen in the red at −0.05%. The spread between best and worst screen narrowed to 2.26 percentage points, the tightest of any period in the journal, ahead of Period 8's previous record of 2.92.

CANSLIM Rocket's win was built on breadth rather than a single outsized position. Twelve of its twenty holdings closed higher, led by BE's own +19.97% surge — BE's second straight strong period after rebounding +4.63% in Period 20 from a −12.39% decline in Period 19 — with MU, FIX, NVDA, and INTR each adding between roughly +5% and +9%. Quality Growth's SNDK delivered a double-digit swing of its own, surging +17.17% for its third double-digit move in four periods, while FICO's −19.18% decline remained the period's steepest drop at the single-stock level.

Period 21 Returns: CANSLIM Rocket's Broad Rally Tops a Historically Tight Field

CANSLIM Rocket led at +2.21%, comfortably ahead of Magic Formula's +1.38% — Magic Formula's best result since Period 19's +5.49%. Quality Growth followed at +0.93% and Lynch at +0.78%. Burry Value Screen and Schloss Dividend both closed barely positive at +0.16% and +0.10%, essentially flat relative to the +0.09%/+0.40% moves of the S&P 500 and NASDAQ. Piotroski F-Score was the only screen to close negative, slipping a marginal −0.05%.

CANSLIM Rocket's +2.21% — the best result of any screen this period — was led by BE, which surged +19.97%, from $210.77 to $252.87, contributing approximately +1.00 percentage points at the screen's 5% weight, extending its own reversal after Period 19's −12.39% and Period 20's +4.63% rebound. MU added +8.98% (+0.45 points) after debuting with a loss in Period 20, and FIX gained +6.03% (+0.30 points), a full reversal of its −8.27% decline last period. NVDA rose +5.89% (+0.29 points) and INTR added +5.20% (+0.26 points). APH gained +4.96% (+0.25 points); the position executed a 2-for-1 stock split during the period, and the return reflects the split-adjusted price. HALO added +4.59% (+0.23 points) and CLS rose +4.57% (+0.23 points), also reversing a Period 19 loss. LRCX, AGI, ARQT, and LUXE each added smaller gains, the latter shared with Piotroski F-Score. Against these, GLBE fell −3.95% (−0.20 points), the screen's largest actual drag, and AVGO declined −2.96% (−0.15 points). PAAS fell −2.89% (−0.14 points), shared with Lynch, and MPWR eased −2.58% (−0.13 points). ETON and LLY each declined roughly −2.2%, and INOD and ANET each fell smaller amounts. Twelve of twenty retained positions closed positive — the screen's best breadth of the period. No names exited or entered, holding CANSLIM Rocket at twenty names for a second straight fully static period. The result lifts CANSLIM Rocket's cumulative return to +10.79% from +8.40%.

Breadth, not a single outsized winner, decided this period's best return: twelve of CANSLIM Rocket's twenty positions closed higher, a wider base of gains than any other screen posted in Period 21.

Quality Growth's +0.93% was led by SNDK, which surged +17.17%, from $1,484.98 to $1,740.00, contributing approximately +1.43 percentage points at the screen's 8.33% weight — the largest single-position contribution of any screen this period. SKHY added +9.91% (+0.83 points), a name shared with Lynch, and PAYS gained +4.34% (+0.36 points), reversing its own Period 20 loss of −8.52% after a +6.99% gain in Period 19 — its third flip in three periods. INCY rose +1.91% (+0.16 points), shared with Burry Value Screen, and NBIX, RDDT, and APP each added smaller gains of +1.03%, +0.95%, and +0.88%. Against these, FICO collapsed −19.18% (−1.60 points), the screen's largest drag by far, and SEZL fell −2.85% (−0.24 points) after leading the screen in each of the prior two periods. MNTN declined −2.12% (−0.18 points) and AUPH eased −1.29% (−0.11 points), the latter shared with Burry Value Screen. Eight of twelve retained positions closed positive. No names exited; DRD enters the screen for Period 22 — a name already shared by Burry Value Screen and Magic Formula, forming the journal's third three-way overlap — growing Quality Growth from twelve to thirteen names.

Magic Formula's +1.38%, the period's second-best result, was led by HAFN, which gained +8.85%, from $8.47 to $9.22, contributing approximately +0.63 percentage points at the screen's 7.14% weight, in its first full period on the screen after entering in Period 20. TRMD added +7.85% (+0.56 points), also in its first full period, and DHT rose +6.15% (+0.44 points). INSW gained +5.76% (+0.41 points), shared with Burry Value Screen, and TNK added +5.26% (+0.38 points). ADMA rose +3.00% (+0.21 points), the three-way overlap it shares with Burry and Lynch, and OGC gained +1.80% (+0.13 points), shared with Lynch. Against these, ERO fell −10.12% (−0.72 points), the screen's largest drag by a wide margin and a sharp acceleration of its own decline after Period 19's +16.63% gave way to Period 20's −1.50%. BVN declined −3.47% (−0.25 points) and FHI fell −3.12% (−0.22 points), and CGAU eased −2.22% (−0.16 points). DDS exited at the sell fee for a flat −0.10% (−0.01 points) — a striking divergence from Burry Value Screen, which held DDS the entire period and watched it gain +5.87%, missing the rally entirely by selling into it. Eight of fourteen retained positions closed positive. DDS exited; BLBD enters the screen for Period 22, holding Magic Formula at fourteen names. The result lifts Magic Formula's cumulative return to +4.27% from +2.84%, its third straight period in positive territory after eighteen consecutive periods underwater through Period 18.

Lynch's +0.78% was led by SKHY, which gained +9.91%, from $161.04 to $177.00, contributing approximately +0.62 percentage points at the screen's 6.25% weight — a move shared with Quality Growth that made SKHY the largest single gain among the period's overlap positions. HRMY added +7.75% (+0.48 points), shared with Burry Value Screen, and PLMR rose +3.76% (+0.23 points). PLGO gained +3.26% (+0.20 points), shared with Schloss Dividend, and ADMA added +3.00% (+0.19 points), the three-way overlap with Burry and Magic Formula. CVE rose +2.50% (+0.16 points) and OGC added +1.80% (+0.11 points), the latter shared with Magic Formula. Against these, BZ fell −4.94% (−0.31 points), the screen's largest drag and a sharp reversal from Period 20's +11.60% — the largest single-position gain of that period now flips to its counterpart's largest loss. PDD declined −4.06% (−0.25 points) and ATAT fell −3.21% (−0.20 points), and ONON eased −2.98% (−0.19 points) in its first full period after entering in Period 20. PAAS fell −2.89% (−0.18 points), shared with CANSLIM Rocket, and SKWD declined −1.63% (−0.10 points). Nine of sixteen retained positions closed positive. No names exited or entered, holding Lynch at sixteen names for its first fully static period since it began tracking overlap positions.

Burry Value Screen's +0.16% was led by EXEL, which gained +8.37%, from $54.45 to $59.01, contributing approximately +0.21 percentage points at the screen's 2.56% weight. HRMY added +7.75% (+0.20 points), shared with Lynch, and DDS rose +5.87% (+0.15 points) — the position Magic Formula exited at the start of the period and missed entirely. INSW gained +5.76% (+0.15 points), shared with Magic Formula, and CRUS added +4.36% (+0.11 points). ADMA rose +3.00% (+0.08 points), the three-way overlap, and ZM, CPRT, GNTX, INCY, TDW, MLI, and WSO each contributed smaller gains between +1.41% and +2.95%. Against these, UTHR fell −5.40% (−0.14 points), the screen's largest drag, and RMD declined −4.98% (−0.13 points). CNS fell −3.41% (−0.09 points), and NTES, HLNE, SII, LRN, and SNA each declined between −2.26% and −2.83%. Seventeen of thirty-nine retained positions closed positive — less than half, though the gains outweighed the losses in aggregate. No names exited; TGS enters the screen for Period 22, a name Burry Value Screen last held at the very start of the journal before exiting it in Period 1, growing the screen from thirty-nine to forty names.

Schloss Dividend's +0.10% was led by GGB, which gained +8.28%, from $4.59 to $4.97, contributing approximately +0.64 percentage points at the screen's 7.69% weight — GGB's second straight double-digit-equivalent gain after Period 20's +6.00% reversal from Period 19's −8.65% decline, now three periods removed from its low. TX added +5.76% (+0.44 points), and PLGO rose +3.26% (+0.25 points), shared with Lynch. DAC gained +3.04% (+0.23 points), and JOYY, CHRD, and AGO each added smaller gains. Against these, VSNT fell −5.88% (−0.45 points), the screen's largest drag, and MTH declined −5.25% (−0.40 points). ATHM fell −3.50% (−0.27 points) and LEN declined −3.19% (−0.25 points), and VIPS eased −2.22% (−0.17 points) in its first full period after entering in Period 20. THO was roughly flat at −0.10% (−0.01 points). Seven of thirteen retained positions closed positive. No names exited; TSN enters the screen for Period 22, growing Schloss Dividend from thirteen to fourteen names.

Piotroski's −0.05% — the only screen to close negative this period — saw API lead, gaining +3.41%, from $4.10 to $4.24, contributing approximately +0.24 percentage points at the screen's 7.14% weight, a full reversal after API was the screen's largest drag in both Period 19 (−6.03%) and Period 20 (−5.96%). SD added +2.65% (+0.19 points) and IIPR rose +1.58% (+0.11 points). TRC and WGO each gained +1.42% and +1.41% (+0.10 points apiece), the latter reversing its own −3.71% decline from Period 20. Against these, MOMO fell −6.12% (−0.44 points), the screen's largest drag, and CYD declined −2.04% (−0.15 points). NOAH fell −1.75% (−0.12 points) and RLX declined −1.64% (−0.12 points). GASS, IPI, and KE all exited at the sell fee for a flat −0.10% each (−0.01 points apiece) — three exits in a single period, the most of any screen this period. Seven of fourteen retained positions closed positive. VISN enters the screen for Period 22, trimming Piotroski from fourteen to twelve names after the three departures.

Retention: Five Screens Hit Perfect Marks as Piotroski's Three Exits Widen the Spread

Period 21 saw Burry Value Screen, Schloss Dividend, Lynch, CANSLIM Rocket, and Quality Growth all post perfect 100% retention — the second-highest count of any period in the journal, trailing only Period 12's six. Magic Formula held a strong 92.9%, losing just one of fourteen names. Piotroski F-Score, by contrast, posted the period's lowest mark at 78.6% after exiting three of its fourteen positions, its steepest single-period turnover since Period 20's own four-screen sweep of perfect scores gave way to this reversal.

CANSLIM Rocket and Quality Growth both climbed into the perfect-retention tier this period, while Burry Value Screen, Schloss Dividend, and Lynch held there. Piotroski F-Score fell hardest, from a share of first place at 100% to last place at 78.6%, and Magic Formula improved slightly from 91.7% to 92.9%. Even with five screens posting perfect scores — one more than Period 20's four — the retention spread widens to 21.4 points, up sharply from Period 20's 8.3, because Piotroski's turnover pulled the range's floor down further than the extra perfect score pulled the ceiling.

Cumulative Scoreboard: Every Screen Holds Its Rank as CANSLIM Rocket Widens Its Cushion Over Lynch

CANSLIM Rocket's +2.21% pushed its cumulative return from +8.40% to +10.79%, widening its lead over fifth-place Lynch — whose own +0.78% lifted its cumulative figure to +8.18% from +7.35% — from 1.05 points to 2.61. Every other screen's rank held exactly where it stood after Period 20: Quality Growth first, Schloss Dividend second, Burry Value Screen third, Magic Formula sixth, and Piotroski F-Score last.

Quality Growth's +0.93% widened its cumulative lead to +33.17% from +31.94%, pushing its margin over second place out to 20.33 points from 19.21. Schloss Dividend's own modest +0.10% held it in second at +12.84%, and Burry Value Screen's +0.16% kept it in third at +12.11%. CANSLIM Rocket's +2.21% — the period's best result — lifted its cumulative return to +10.79% from +8.40%, and Magic Formula's +1.38% lifted its own to +4.27% from +2.84%. Piotroski F-Score's marginal −0.05% deepened its cumulative loss only slightly, to −10.62% from −10.58%, extending its stay in last place.

Both benchmarks posted modest gains again this period. The S&P 500's cumulative return edged up to +13.82% from +13.72%, and the NASDAQ's to +16.79% from +16.33%. Quality Growth's alpha widened to +19.35% against the S&P 500 and +16.38% against the NASDAQ, up from +18.22% and +15.61% — still the only screen with positive cumulative alpha against either benchmark. CANSLIM Rocket posted the sharpest alpha improvement of any trailing screen, narrowing to −3.03%/−6.00% from −5.32%/−7.93%. Magic Formula also improved meaningfully, to −9.55%/−12.52% from −10.88%/−13.49%, and Lynch narrowed to −5.64%/−8.61% from −6.37%/−8.98%. Burry Value Screen's alpha was roughly flat at −1.71%/−4.68% versus −1.79%/−4.40%, and Schloss Dividend held near −0.98%/−3.95% from −0.99%/−3.60%, the closest of the six trailing screens to flipping positive against the S&P 500. Piotroski F-Score's alpha widened marginally to −24.44%/−27.41% from −24.30%/−26.91%.

Overlap: DRD Forms a Third Three-Way Position as DDS Drops Out

The September 5 snapshot shows thirteen stocks in two or more screens, down from fourteen on August 29, as Magic Formula's exit of DDS removes it from Burry Value Screen's only shared pairing with that name, while Quality Growth's addition of DRD — already held by Burry Value Screen and Magic Formula — creates the journal's third three-way overlap alongside ADMA and FSM. Every other overlap pairing carried over unchanged from Period 20.

Of the pairs already in place, ADMA's +3.00% lifted all three of its holders together, and SKHY's +9.91% — the largest gain among the period's overlap positions — gave a matching boost to both Lynch and Quality Growth, the widest-reaching gain of the period in percentage terms. HRMY's +7.75% helped Burry Value Screen and Lynch alike, and FSM's modest +0.41% gave a small lift to all three of its holders. INCY's +1.91% helped Burry and Quality Growth, and INSW's +5.76% and PLGO's +3.26% each lifted their respective pairs — Burry with Magic Formula, and Schloss Dividend with Lynch. OGC's +1.80% helped Lynch and Magic Formula together, and LUXE's +0.26% gave a small lift to Piotroski and CANSLIM. On the downside, RELY's −1.43% weighed on Burry and Lynch, AUPH's −1.29% trimmed both Burry and Quality Growth, and PAAS's −2.89% weighed on Lynch and CANSLIM Rocket alike. DRD's −0.66% affected only Burry Value Screen and Magic Formula this period, since Quality Growth's position doesn't take effect until Period 22.

What Period 21 Tells You

Breadth wins as reliably as magnitude. CANSLIM Rocket's +2.21% — the best result of the period — came from twelve of its twenty positions closing higher, not from one outsized winner. BE's +19.97% was the largest single move on the screen, but it needed help from eleven other gainers to produce the period's top return.

A record-tight spread means real convergence, not a fluke. The 2.26-point gap between CANSLIM Rocket's +2.21% and Piotroski's −0.05% is the narrowest this journal has recorded, edging out the 2.92-point gap that stood as the record since Period 8. Seven independently run books ranging from twelve to forty names landed within a couple of points of each other for the second time in three periods.

A single-stock decline can still be the sharpest story in a strong period. FICO's −19.18% drop was the steepest of any position this period, cutting deep enough into Quality Growth's return (−1.60 points) to offset most of SNDK's +17.17% surge (+1.43 points) and hold the screen to a modest +0.93% gain even as its two biggest movers each swung by double digits.

Standings can hold while the gaps between them move. CANSLIM Rocket's +2.21% didn't change a single cumulative rank — every screen finished Period 21 exactly where it started it — but it more than doubled the cushion separating fourth-place CANSLIM Rocket from fifth-place Lynch, from 1.05 points to 2.61. An unchanged scoreboard can still be telling a very different story underneath.