COST's current daily % reading and what that signal has historically been followed by.
This page covers Costco (COST) — its current daily % reading and the measured historical record of what COST daily % extremes were followed by.
How to read this. These figures are measured only on instruments currently in our coverage — a set of companies that survived. Signals that appear to have 'worked' on the downside are conditioned on these names having recovered; a company that fell and never came back would not be here to measure. Read every number below as a property of this surviving sample, not a universal rule, and never as advice.
All figures are ‘excess’ returns — measured relative to each instrument’s own historical drift, not relative to the market. This is not alpha and not a market-beating claim; it isolates the signal from the instrument’s background trend. Measured from the first day each signal appeared (not its most extreme point), so it reflects what was knowable in real time.
daily % showed no measurable forward signal. Across the full sample, episodes on this measure were followed by returns statistically indistinguishable from each instrument’s own drift — we report this as a null result rather than hide it.
When COST was overbought / at a high extreme
Across 169 past episodes where COST was overbought on this signal, the close 20 sessions later beat COST’s own trailing drift by 0.92 percentage points on average (54% of episodes beat drift).
| horizon | excess vs own drift | beat-drift rate | episodes with complete horizon |
|---|---|---|---|
| 1 session | +0.24% | 54% | 169 |
| 5 sessions | +0.40% | 57% | 169 |
| 20 sessions | +0.92% | 54% | 169 |
When COST was oversold / at a low extreme
Across 165 past episodes where COST was oversold on this signal, the close 20 sessions later beat COST’s own trailing drift by 1.08 percentage points on average (53% of episodes beat drift).
| horizon | excess vs own drift | beat-drift rate | episodes with complete horizon |
|---|---|---|---|
| 1 session | -0.14% | 47% | 165 |
| 5 sessions | +0.42% | 53% | 165 |
| 20 sessions | +1.08% | 53% | 165 |
See COST’s current price, RSI, moving averages and 52-week range →