Weekly Market Review - October 17, 2026

Prepared by Sangyong’s Market Intelligence

Executive Summary

Week Character: Global Risk-Off

The week of October 12-16, 2026 was characterized as Global Risk-Off. US markets finished moderately lower with the S&P 500 at -1.89% and the Nasdaq at -4.06%. 1 of 7 Magnificent 7 stocks advanced on the week. Korean markets closed dramatically lower, with KOSPI at -11.22% and KOSDAQ at -6.41%.

The 10Y Treasury yield fell 3 bps to 5.19%, with little impact on equity multiples. The Korean won strengthened 0.05% against the dollar — a negligible FX effect.

Key stat: Broad losses — risk-off positioning was rewarded.

Weekly Performance Summary

U.S. Magnificent 7

Stock	Symbol	Mon Open	Fri Close	Weekly Change	Trend
Apple	AAPL	$341	$343	+0.73%	🟢
Microsoft	MSFT	$541	$529	-2.24%	🔴
Alphabet	GOOGL	$353	$341	-3.44%	🔴
Amazon	AMZN	$260	$250	-3.67%	🔴
NVIDIA	NVDA	$226	$214	-5.39%	🔴
Meta	META	$743	$709	-4.53%	🔴
Tesla	TSLA	$378	$355	-6.17%	🔴

Korean Market Leaders

Stock	Symbol	Mon Open (₩)	Fri Close (₩)	Weekly Change	Trend
Samsung Elec.	005930	₩251,000	₩217,000	-13.55%	🔴
SK Hynix	000660	₩1,605,000	₩1,265,000	-21.18%	🔴
Hyundai Motor	005380	₩318,500	₩314,000	-1.41%	🔴

Indices

Index	Mon Open	Fri Close	Weekly Change	Trend
S&P 500	7,807.24	7,659.44	-1.89%	🔴
Nasdaq	27,245.90	26,140.03	-4.06%	🔴
Dow Jones	51,850.55	52,002.41	+0.29%	🟢
KOSPI	6,384.24	5,668.05	-11.22%	🔴
KOSDAQ	849.19	794.78	-6.41%	🔴

Currency (KRW/USD)

Monday: ₩1,335
Friday: ₩1,334
Weekly Change: -0.05% (KRW strengthened — USD weaker)
Impact: Negligible FX impact this week.

U.S. 10-Year Treasury Yield

Monday: 5.22%
Friday: 5.19%
Weekly Change: -3 bps
Implication: Stable yields — no rate-driven equity repricing this week.

Weekly Trends and Themes

1. US Market Performance

S&P 500: -1.89% | Nasdaq: -4.06% | Dow: +0.29%

The S&P 500 fell -1.89% for the week, with Nasdaq leading the decline at -4.06%. Defensives held up better; the decline was growth/tech-driven.

Magnificent 7: 1 of 7 Mag7 stocks advanced. Best: Apple (+0.73%), worst: Tesla (-6.17%).

Takeaway: Consolidation week — no tactical change needed.

2. Korean Market Performance

KOSPI: -11.22% | KOSDAQ: -6.41% (weekly)

KOSPI fell -11.22% — a significant weekly decline; avoid new entries until price stabilizes.

KOSDAQ dramatically lower (-6.41%), outperforming KOSPI — risk appetite favoring small/mid caps.

Among Korean blue chips: Hyundai led (-1.41%), SK Hynix lagged (-21.18%).

Takeaway: Weak week — wait for stabilization before new entries.

3. Currency Impact (KRW/USD)

Weekly KRW Move: -0.05% ₩1,335 → ₩1,334

The won was virtually unchanged (-0.05%) — no currency-driven distortion to Korean equity returns this week.

Investor Implication: Neutral for Korean stock investors denominated in USD.

Export sector note: Stable KRW — no meaningful FX-driven earnings revision expected.

4. Treasury Yields

10Y: 5.22% → 5.19% (-3 bps)

The 10Y Treasury yield held steady at ~5.19% (-3 bps for the week) — no yield-driven repricing of equities.

Market Implication: Stable rates support growth stock multiples.

5. Key Weekly Observation

US outperformed Korea by 9.3pp this week — US macro strength or global risk rotation toward dollar assets is the likely driver.

Best and Worst Performers

Best (Weekly Upside Movers):

Apple: +0.73% █
Hyundai: -1.41% ██
Microsoft: -2.24% ████
Alphabet: -3.44% ██████
Amazon: -3.67% ███████

Worst (Weekly Declines):

Tesla: -6.17% ████████████
Samsung: -13.55% ████████████████████
SK Hynix: -21.18% ████████████████████

Commentary:

SK Hynix was the clear laggard at -21.18% — a decline of this magnitude warrants a fundamental review. Check whether this reflects a company-specific negative (guidance cut, regulatory headwind) or macro pressure.

1 of 10 stocks advanced. Negative breadth — more stocks declining than advancing.

Weekly Review Compiled: October 17, 2026 at 12:10 PM Analysis Period: October 12 - 16, 2026 Data Sources: Daily market reports, Naver Finance, Yahoo Finance, FRED