Norway has an open electric market, integrated with the other Nordic countries. Export and import is routine over the direct power links to Sweden, Denmark, and the Netherlands. The market is handled by Nord Pool, and has 5 price zones in Norway. Financial future contracts are traded at NASDAQ OMX. Many of the hydroelectric plants in Norway are easily adjustable and can adapt well to variations in demand, and hence in price, but frequency stability is not satisfactory, and Statnett works with producers to minimize sudden changes in power flow. On a normal day, when price is low during nighttime, Norway normally imports power, and exports during daytime when the price is higher. Maintaining the grid in the harsh Norwegian nature is a compromise between stability desires and economy, and outages are expected in these circumstances. About 70% of the grid is without grounding; called IT-nett.