Yes — and it is measurably calmer since the 2015 reform.
Six banks were fined roughly $4.3bn for coordinating on this benchmark between 2008 and 2013. On 15 February 2015 the calculation window was widened from 60 seconds to five minutes to stop it. Comparing before and after, against ordinary hours in the same period: activity is unchanged (128% → 125%) while the directional pull fell by about a third, in 8 of 10 markets. Busy as ever; leaning less. That matches what tick-level researchers found. Held loosely — 8 of 10 is suggestive, not proof, and an hourly bar is a blunt instrument for a five-minute event.
| Market | In the window | Rest | z | Movement | Samples |
|---|---|---|---|---|---|
| Silver (XAG/USD) | 53.5% | 49.2% | 6.0 | 114% of normal | 5,196 |
| USD/CAD | 46.8% | 49.8% | -4.5 | 139% of normal | 5,910 |
| EUR/JPY | 52.9% | 50.6% | 3.2 | 113% of normal | 5,218 |
| NAS100 | 55.7% | 52.2% | 2.9 | 163% of normal | 1,698 |
| USD/JPY | 52.5% | 50.3% | 2.8 | 84% of normal | 4,553 |
| GBP/JPY | 52.7% | 50.9% | 2.4 | 98% of normal | 4,150 |
CFTC on the $1.4bn penalties · Evans, O’Neill, Rime & Saakvitne
Every claim here reduces to a window on the clock or the calendar, so it can simply be checked. We compare the claimed window against the rest of the week on 23 years of hourly data across 19 markets, measuring two separate things the folklore tends to conflate: direction (does the window close higher more often?) via a two-proportion z-test, and movement (is the average move bigger or smaller?). A window can be perfectly ordinary in direction and genuinely quieter in movement — saying which is the entire point.
The bar here is |z| ≥ 2, deliberately more lenient than the |z| ≥ 3 this site applies to its own numbers: when testing someone else's claim, failing to reject it even at a lenient bar is the stronger statement.