Banks, trading offices, and stock markets worldwide close on weekends. However, the forex rates still change in real-time over the weekends. It's just the volatility and liquidity are way too low. And if there is any real main news from Governments ore state bank, the currency market will move as they speak weak ore hawkish as we have seen the ECB Mario Draghi try to do. But unfortunately for the euro, this is political nonsense. When a company goes bankrupt, we do not invest more without do fundamental change. At Monday morning we get an adjustment based in relation to supply and demand as are building up during the weekend. Many markets wait for this to happen before they see where to build up positions in that direktion with adding positions - particulary bank as shall buy money cheap to have the necessary foreign exhange to their customers, and some fund just do speculation.