COST monthly performance report
Monthly COST research: returns, drawdown, relative strength, seasonality, and key stats.
COST monthly report
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Key takeaways
- Costco (COST) closed August 2026 at $941.99, down 1.04% for the month and −0.17% over the trailing 12 months.
- Year-to-date, COST is +9.24%, underperforming the S&P 500 which has returned +12.89% YTD.
- The stock is trading −1.66% versus its 200-day moving average ($957.88), a cautious technical signal.
- Over the past three years, COST has underperformed the S&P 500 by −1.65%, with a relative strength index reading of 98.8.
- Win rate over the trailing 39 months stands at 53.8% — 21 positive months versus 18 negative months.
Costco ended August 2026 at $941.99, posting a monthly return of −1.04%. The S&P 500 returned +3.05% over the same window, leaving relative performance at −4.09%.
The current quarter stands at +0.90% (Q3 2026 (QTD)), while medium-term trend remains soft: price is −1.66% versus the 200-day moving average ($957.88).
Year-to-date, COST is +9.24% against SPY +12.89%, a gap of −3.65%. The stock is currently −14.09% below its 52-week high, with maximum 3-year drawdown at −21.07%.
| Period | COST | S&P 500 (SPY) | Excess return |
|---|---|---|---|
| 1 Day | −0.62% | −0.20% | −0.42% |
| 1 Week | −2.54% | +3.90% | −6.45% |
| 1 Month | −1.04% | +3.05% | −4.09% |
| 3 Months | −7.15% | +7.11% | −14.26% |
| 6 Months |