S&P 500 Falls 0.87% on 20 August 2026 as Yields Rebound and Walmart Drops 9.15%

S&P 500 close: 7,641.16 (-0.87%) Breadth: 9 of 11 sectors lower Sentiment: bearish

The S&P 500 closed at 7,641.16 on 20 August 2026, down 66.82 points or 0.87%, after Wednesday's Treasury buyback relief faded and the 30-year yield returned to 5.24%. Walmart WMT.US fell 9.15% to $103.84 after US same-store sales grew 2.6% against a 3.7% forecast, the slowest pace since the fourth quarter of 2020. The Dow fell 703.84 points, or 1.32%, with GS.US and WMT.US alone accounting for roughly 185 of those points.

What moved the index

• Health care: XLV -1.87%, worth roughly 17 bps of the 87 bps index decline. MRNA.US fell 23.55% after a 177% advance on Wednesday on its Phase 3 melanoma vaccine result, and partner MRK.US fell 2.11% after gaining 12.5% that same session.
• Consumer discretionary: XLY -1.61%, roughly 16 bps. AAP.US fell 24.55% on flat second-quarter revenue of $2.0bn and a deceleration in DIY spending, with HD.US -2.85% and AMZN.US -2.16% adding to the drag.
• Financials: XLF -0.92%, roughly 12 bps, as the 30-year yield rose 4 bp to 5.24% and the 10-year rose 4 bp to 4.70%. GS.US -1.93%, AXP.US -2.57% and JPM.US -1.60%.
• Technology: XLK -0.29%, roughly 11 bps and the shallowest decline of any sector. NVDA.US -0.33%, MSFT.US -0.47% and CRM.US -0.32% left the largest index weight close to unchanged.

Those four sectors account for roughly 56 of the 87 bps index move. Industrials at 8 bps, communication services at 6 bps and staples at 6 bps lift the named total near 76 bps, with energy the only offset at roughly 1 bp. The residual is breadth. The Russell 2000 fell 1.34%, worse than either the S&P 500 or the Nasdaq.

Session highlights

• WMT.US -9.15% to $103.84 on second-quarter revenue of $187.9bn against a $186.8bn estimate. Adjusted earnings of 81 cents beat the 74-cent consensus and full-year sales growth guidance rose to 4% to 5%, but third-quarter guidance of 62 to 64 cents landed under the 68-cent estimate.
• Treasury Secretary Scott Bessent lifted long-dated buybacks from $2bn to at least $4bn on Wednesday, saying yields did not reflect underlying fundamentals. The 10-year gave back that move within a session, closing at 4.70%.
• Bitcoin traded near US$72,789, its highest since 1 June, and IBIT +6.24%. Listed proxies followed: MARA.US +15.54%, RIOT.US +8.26%, MSTR.US +7.81% and COIN.US +7.58%.
• DE.US +6.94% to $620.94 on fiscal third-quarter earnings of $5.10 per share and revenue of $12.61bn, with double-digit percentage gains in construction and forestry offsetting weaker agricultural machinery.
• Aerospace and defense names fell together: AVAV.US -7.50%, KTOS.US -7.23%, MRCY.US -6.93%, KRMN.US -6.60% and FLY.US -6.60%. SPCX.US -4.05% on a share unlock.

Sector scorecard

• Best: Energy XLE +0.27%
• Worst: Health Care XLV -1.87%
• Dispersion (best minus worst): 2.14 pts
• Only energy (+0.27%) and real estate (+0.20%) closed higher. Crude proxy USO +2.77% and Brent above US$93 a barrel followed President Trump's pledge to isolate Iran economically over stalled Strait of Hormuz talks.

Top movers

After-hours earnings

ROST.US reported second-quarter results after the 4:00pm ET bell, covering the 13 weeks to 1 August 2026. Earnings came in at $2.66 per share against company guidance of $1.85 to $1.93, sales rose 13% to $6.3bn and comparable store sales rose 10% on customer traffic. About $253m of IEEPA tariff refunds contributed roughly 405 bp of operating margin and about 60 cents of the per-share result. Full-year guidance rose to $8.61 to $8.77 per share and planned store openings rose to 115. ROST.US closed the regular session at $228.99, down 2.43%, before the release.

ROST.US comparable sales of 10% ran against WMT.US at 2.6% on the same US consumer. Walmart management described shoppers making trade-offs against high fuel costs; Ross credited customer traffic.

Notable announcements

• COTY.US reported a fourth-quarter loss of 2 cents per share against a 1-cent estimate, with sales near $1.3bn, and guided first-quarter fiscal 2027 revenue to a low to mid single-digit percentage decline.
• NDSN.US +8.00% to $334.70 after record fiscal third-quarter sales of $817.7m, up 10%, and raised full-year sales and adjusted earnings guidance.
• Initial jobless claims for the week to 15 August came in at 206,000, down 6,000 on the prior revised week. The four-week average rose 4,250 to 204,000 and the insured unemployment rate held at 1.2%.

At the US close (5:00pm ET)

Next session catalysts (ET)

• Fri 21 Aug, 9:45am S&P Global flash US manufacturing, services and composite PMIs for August
• Fri 21 Aug, 1:00pm Baker Hughes rig count
• Mon 24 Aug, 8:30am Chicago Fed national activity index for July
• Tue 25 Aug Conference Board consumer confidence and July new home sales; Fed's Barkin speaks; INTU.US reports
• Wed 26 Aug Q2 GDP second estimate, July PCE, July durable goods orders and personal income; NVDA.US reports after the close alongside CRM.US, CRWD.US and SNPS.US
• Thu 27 to Sat 29 Aug Jackson Hole symposium, with Fed Chair Kevin Warsh delivering his first keynote on Friday 28 August

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