Should You Wait for Tokyo Instead of Trading the Sunday Open?
True — and it is the best example of why a big number can be untradeable.
The Sunday reopen produces the most extreme readings in our data: USD/CHF closes higher 62.8% of its Sunday hours against 49.8% on a Monday. Sunday is under 4% of the windows we can test and supplies 6 of the 20 strongest. It is also the widest-spread moment of the week. Our minute archive carries the ask as well as the bid for 10 FX pairs, and the first minute of the reopen costs a median 7.39× each pair’s own quiet late afternoon (wider in 10 of 10); EUR/USD opens the week at 4.5 pips against 0.3 at a recent midday.
And most of the lean is not the price. A spread that is widest at the reopen and narrows through its first hour raises the bid by itself, and our hourly numbers, like most charts, are built from the bid. In that first hour USD/CHF’s bid closes up 62.6% of weeks, its ask 34.0%, and the midpoint between them 48.6% (z -1.1), inside our bar. Across the 10 pairs the bid rises past the bar in 10, the ask falls past it in 9, and the midpoint leans up past it in 3. Two hours later, once the spread has settled, the bid and ask up-rates sit a median 2.6 points apart against 20.15 at the reopen. So the advice survives, for a better reason than the folklore gives: waiting for Tokyo does not skip an edge, it mostly skips a number the quote builds by itself. Metals, indices and crypto are not in the minute archive, so for them it stays unchecked. The measurement →
What the data shows
| Market | In the window | Rest | z | Movement | Samples |
|---|---|---|---|---|---|
| USD/CHF | 62.8% | 49.8% | 10.3 | 243% of normal | 1,759 |
| USD/JPY | 61.9% | 50.9% | 10.4 | 220% of normal | 2,483 |
| NZD/USD | 55.0% | 50.1% | 5.0 | 219% of normal | 2,850 |
| GBP/JPY | 60.2% | 51.2% | 8.2 | 193% of normal | 2,273 |
| EUR/JPY | 58.7% | 51.1% | 7.6 | 192% of normal | 2,812 |
| AUD/USD | 54.9% | 50.2% | 4.9 | 182% of normal | 2,970 |
Who says it
How this was measured
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.