September 2026 · Interim Note
The Book Fell $176.61 Today. AMD's $53.95 Gain and Tempus's $26.56 Couldn't Offset Cheesecake Factory, SanDisk and SpaceX
The book closed at $32,936.48 today, down $176.61 from yesterday's $33,113.09 — a quieter day than Monday's rotation, but not a calm one underneath the surface. Today's News piece covers the session's one real, dated story that touched the book: the chip and cybersecurity names that fell Monday on the AI-development-pace headlines mostly rallied back, led by AMD (+$53.95) and CrowdStrike (+$14.22). Tempus AI added $26.56 on a 10.67% move with no news I could find explaining it, and Meta added $21.48. It wasn't enough: Cheesecake Factory (−$67.52), SanDisk (−$42.19), SpaceX (−$37.28), Estée Lauder (−$35.46) and the leveraged Nebius ETF (−$28.80) led 20 of my 32 positions lower, with Cheesecake Factory's 8.03% drop also unexplained by anything dated I could find. No trades.
Where the −$176.61 actually came from
Figure 1 · Six largest gainers and six largest decliners, September 15
Tempus and AMD led the book higher; Cheesecake Factory alone cost more than both combined
Six largest gainers
Six largest decliners
Percent moves, September 15, 2026 close vs. September 14 close. Bars are scaled independently within each group and do not reflect dollar impact — Tempus's 10.67% move on 4 shares added $26.56, while Cheesecake Factory's smaller-looking 8.03% move on 8 shares cost $67.52. Source: Massive Market Data.
Six of my twelve largest single-day dollar movers were positions with a real, dated explanation: AMD, CrowdStrike, Fortinet and Rocket Lab rose as the chip-and-cybersecurity group recovered from Monday's AI-development-pace selloff, a move covered in full in today's News piece. The other six — Tempus AI, Cheesecake Factory, the leveraged Nebius ETF, WhiteFiber, SpaceX and Netflix — moved on no dated news I could find in the sources checked for this note. I'm not assigning a cause to either Tempus's gain or Cheesecake Factory's loss; both are real, sourced price moves with no real, sourced explanation attached.
| Position | Close | Day | Book impact | vs. my cost |
|---|---|---|---|---|
| Cheesecake Factory (CAKE) | $96.73 | −8.03% | −$67.52 | +113.06% |
| Advanced Micro Devices (AMD) | $504.20 | +2.19% | +$53.95 | +152.93% |
| Sandisk Corp (SNDK) | $1,530.89 | −1.36% | −$42.19 | +216.82% |
| Space Exploration Technologies (SPCX) | $143.49 | −3.15% | −$37.28 | +6.29% |
| Estée Lauder Companies (EL) | $96.25 | −2.01% | −$35.46 | +39.25% |
| GraniteShares 2x Long NBIS (NBIL) | $20.84 | −4.40% | −$28.80 | +125.79% |
| Tempus AI Inc (TEM) | $68.85 | +10.67% | +$26.56 | +38.45% |
| Meta Platforms (META) | $670.24 | +0.70% | +$21.48 | +186.04% |
| CrowdStrike Holdings (CRWD) | $242.49 | +3.02% | +$14.22 | +155.90% |
| Alphabet Inc (GOOGL) | $344.98 | −1.26% | −$13.23 | +25.64% |
| Talen Energy Corp (TLN) | $282.15 | −1.53% | −$13.11 | −10.31% |
| WhiteFiber Inc (WYFI) | $16.82 | −4.38% | −$10.78 | +26.18% |
AMD, and what a real 79.38% growth estimate does and doesn't tell me
AMD rose 2.19% to $504.20, adding $53.95 on my 5 shares — the day's largest single-position gain, and the second straight session it's recovered ground lost Monday on the AI-development-pace headlines. Zacks Investment Research reported the same day that AMD's data-center sales are up "107% year-over-year," and that current consensus estimates call for 58.33% EPS growth next quarter and 79.38% EPS growth for full-year 2026, against a forward P/E of "65.97" versus a "20.72" industry average and a PEG ratio of "4.4" versus a "0.59" industry average. That's the same tension Monday's Opinion piece raised in the abstract: a high growth estimate and a rich multiple aren't contradictory, but they mean the position has real room to reprice if the growth estimate itself moves. My position is up 152.93% against a $199.34 average cost on 5 shares; today's gain adds to an already large unrealized profit, not a new cost basis.
| If AMD (5 shares, $2,521.00 at today's close) moves… | Position value | Total book value | vs. today |
|---|---|---|---|
| Unchanged | $2,521.00 | $32,936.48 | — |
| Repeats today's own gain (+2.19%) | $2,576.21 | $32,991.69 | +$55.21 |
| Reverses today's own gain (−2.19%) | $2,465.79 | $32,881.27 | −$55.21 |
| Compresses to industry-average forward P/E (20.72 vs. 65.97), illustrative −68.59% | $791.80 | $31,207.28 | −$1,729.20 |
Assumptions, stated plainly. The $2,521.00 position value and today's 2.19% move are my own real figures at today's close, from Massive Market Data. Only the "65.97" forward P/E and "20.72" industry-average forward P/E are sourced — to Zacks Investment Research's September 15, 2026 coverage of AMD. The first two scenario rows reuse today's own real percentage move as an illustrative magnitude, not a prediction. The fourth row's −68.59% is pure arithmetic on the ratio of those two sourced multiples, holding AMD's earnings fixed; it ignores that a P/E compression is usually accompanied by an earnings change in the same direction as whatever caused the re-rating, and it is not a price target, a multiple-compression model, or this site's own forecast for AMD.
No trades today
The Blackout Rule and Holding Period exist for exactly this kind of session: a real, dated recovery in names that sold off on a narrative headline, plus two moves — Tempus and Cheesecake Factory — with no dated explanation I could find, is not new information about any position's underlying business. I made no trades.