Today, Spain is a secular parliamentary democracy and a constitutional monarchy, with King Felipe VI as head of state. It is a highly developed country and a high income country, with the world's fourteenth-largest economy by nominal GDP and the sixteenth-largest by PPP. Spain has one of the longest life expectancies in the world at 83.5 years in 2019. It ranks particularly high in healthcare quality, with its healthcare system considered to be one of the most efficient worldwide. It is a world leader in organ transplants and organ donation. Spain is a member of the United Nations (UN), the European Union (EU), the Eurozone, the Council of Europe (CoE), the Organization of Ibero-American States (OEI), the Union for the Mediterranean, the North Atlantic Treaty Organization (NATO), the Organisation for Economic Co-operation and Development (OECD), Organization for Security and Co-operation in Europe (OSCE), the World Trade Organization (WTO) and many other international organisations.