The Trading Addict · Issue No. 81 · Wednesday September 16, 2026

The Costco Oil Crisis

Kirkland Signature synthetic oil hits $58 with a 2-pack limit as Middle East war disrupts supply. The 10-year Treasury is back at 5% — the same number that preceded a 15.8% rally in 2023 and a 57% crash in 2007. In 1929, they sang about margin calls. Maria eyes another MU pullback before end-of-month earnings.

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Issue No. 81  •  Wednesday September 16, 2026

The Trading Addict Newsletter by Maria Helmick

In This Issue

You Went to Costco for a Bargain. You Found the Oil Crisis. — Kirkland Signature 10-quart synthetic oil at $58, up from $30. Two-pack limit. Middle East war disrupts Group III base oils.  Jump to this story →
The 5% Flashback: One Time a Rally. One Time a Wreck. — The 10-year Treasury is back at 5%. Oct 2023 launched a 15.8% rally. July 2007 preceded a 57% crash. Same number, very different endings.  Jump to this story →
Wall Street Had a Song. Then the Music Stopped. — Sept 30, 1929: Frank Crumit records 'A Tale of the Ticker' — a comedy about margin calls. Twenty-nine days later, Black Tuesday.  Jump to this story →
Maria's Earnings Plays — Micron (MU) — MU's earnings are end of month. Maria already caught one pullback. Watching for another before the report.  Jump to this story →
Tech & Semi Heatmap · Sep 15 Close — The full board after Tuesday's session.  Jump to this story →
Earnings Watch · Sep 15 — Oct 1 — LEN tonight. AZO Tue. COST Thu. MU end of month.  Jump to this story →
Day 228 · Tue Sep 15 Trading Update — $1M +$29,265 (178 tr). $30K +$1,158 (32 tr). Combined +$31,942. Strong rebound.  Jump to this story →
Today's Live Show — Watch Rob and Nick on YouTube — 9:15 AM & 3:15 PM ET.  Jump to this story →
Maria at Costco holding a Kirkland motor oil jug, Porsche dealership behind her, thinking 'Hmm. Why change the oil? Maybe I should just get a new Porsche instead.' (tap to enlarge)

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Costco · Kirkland Signature

You Went to Costco for a Bargain. You Found the Oil Crisis.

The oil crisis has moved beyond the gas pumps and into Costco. A 10-quart pack of Kirkland Signature full-synthetic motor oil is now listed at about $58, up from previous prices as low as $30, with purchases limited to two packs per customer per week. Even shoppers changing their own oil to save money are getting squeezed.

How the War Reaches Your Garage

"Synthetic" doesn't mean immune to an oil shortage. Many synthetic motor oils use highly refined ingredients called Group III base oils. The United States reportedly imports more than 40% of these oils from the Middle East, where the war has disrupted supplies. Those disruptions reach all the way to the maintenance aisle: Costco has also restricted purchases of certain Mobil 1 motor-oil packs.

Higher Prices, Tighter Budgets

For Costco shareholders, a higher price tag doesn't automatically mean a bigger profit; rising supplier and delivery costs can eat up the difference. For families facing tight budgets, it may mean putting an oil change on hold. When money is short, food on the table comes first.

Maria's Bottom Line

Like everything else, war has a price, and right now, we're paying it in oil. Some companies may absorb the extra cost, while others pass it along. In Costco's case, the customer is picking up the tab. Eventually, you've still got to change your oil. There's no getting around that. You can't count on supplies improving and prices settling back down before it's due, but hopefully we'll see some relief over the next few months. Or maybe it's just a good excuse to go trade your car in!

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10-Year Treasury · Then & Now

The 5% Flashback: One Time a Rally. One Time a Wreck.

The 10-year Treasury yield is back at 5%, and Wall Street has reason to look over its shoulder. The last two visits came in October 2023 and July 2007. One was followed by a powerful stock rally. The other preceded a financial disaster. Same number. Very different endings.

Five percent isn't a crystal ball, but it changes the conversation. Treasuries offer stocks tougher competition for investors' money, while borrowing gets more expensive for homebuyers and businesses. Eventually, somebody feels the squeeze.

2023: Just When Investors Had Had Enough

By October 2023, investors were exhausted by inflation and the prospect of interest rates staying high. On October 23, the 10-year briefly pushed above 5%. By October 27, the S&P 500 was roughly 10% below its summer high. The market looked bruised, and there was plenty to worry about.

But that was close to the turning point. Inflation eased, investors began anticipating eventual Fed rate cuts, and yields retreated. The economy kept going. From its October 27 closing low through year-end, the S&P 500 rallied approximately 15.8%, excluding dividends. Investors who assumed 5% meant the worst was still ahead watched stocks take off.

2007: Stocks Climbed. Trouble Spread.

Rewind to July 20, 2007, the previous visit to 5%. The housing boom was unraveling, but after a turbulent summer, the S&P 500 reached a new peak that October. There was still time to believe the damage could be contained.

It couldn't. Mortgage losses spread, financial institutions buckled, and lending seized up. From its October 2007 peak to March 2009, the S&P 500 fell approximately 57%. The disaster unfolded over months as the financial crisis deepened; crossing 5% hadn't triggered an overnight collapse.

The Twist: Yields Fell Both Times

Falling yields accompanied the late-2023 rally as inflation fears eased. During the financial crisis, yields also fell, but investors were seeking safety while the economy deteriorated. Even seeing the 10-year retreat from 5% won't tell us everything. Why it's falling matters.

Maria's Bottom Line

2023 wasn't that long ago, but this market feels different. Look at what it's taking: war, $100 oil, and one unsettling headline after another. Yet it keeps finding its footing. That resilience means something. So am I supposed to believe a quarter-point rate hike or a 5% Treasury yield is suddenly going to knock it out? I'm not buying that. This market can pull back, but it's going to take more than a quarter point to convince me it's done.

» A MARKET TIDBIT · 1929

Wall Street Had a Song — Then the Music Stopped. Sept 30, 1929: Frank Crumit records 'A Tale of the Ticker,' a comedy about margin calls. Twenty-nine days later, Black Tuesday. Tap to read the full three-page story plus the original lyrics.

» Tap to Read the Full Story »

Maria's Earnings Plays

MU: My Next Move Could Come Before Earnings

MU's earnings aren't until the end of the month, but these market swings have my attention. I've already taken advantage of one pullback, and another could set up our next earnings play sooner than expected.

The market's rise could be a short-term bounce, so I'm watching to see whether it holds. A little more back-and-forth before earnings could give us something to work with.

What am I watching for — and when would I step in?

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» TECH & SEMI HEATMAP · SEP 15 CLOSE

Technology and Semiconductor Heatmap - Sep 15 2026 close (tap to enlarge)

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» EARNINGS WATCH · SEP 15 — OCT 1

Earnings watch calendar Sep 15 to Oct 1 - LEN, AZO, CTAS, PAYX, GIS, COST, DRI, MU, JBL, ACN, NKE (tap to enlarge)

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» DAY 228 · TUE SEP 15 · DAILY TRADING UPDATE

Daily Trading Update Day 228 - Tue Sep 15 2026 - $1M +$29,265 (178 tr) cum $748,606 (+74.86%), $30K +$1,158 (32 tr) cum $25,543 (+85.14%) - Combined +$31,942

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Educational only. Not investment advice. Trading options involves substantial risk. Past performance does not guarantee future results.