Today's swap move explained: The ECB (for example) can sell euros to the Fed in exchange for dollars at the prevailing market rate, at the same time agreeing to buy back said euros at the same rate. The swap refers to the cost to the ECB for doing such, and today's action lowers it 50 bps. "It's a global effort to add dollar liquidity," writes Quint Tatro, hence, dollar down, assets up.