No it's not like direct or indirect correlation, the fundamentals is that once oil prices start surging it strength the CAD index which causes CAD to be stronger than dollar because Canada is a major oil exporting country so their economy actually depends highly on oil prices so but if oil is down and CAD fundamental is good and dollar is down fundamentally it can still favour usdcad sells but if USD is stronger fundamentally and oil is weak and cad is fundamentally weak it will favour usdcad buy