During the 1990s and 2000s, the development of research was hampered by several factors, including: corruption, low funding, and a considerable brain drain. In recent years, Romania has ranked the lowest or second-lowest in the European Union by research and development spending as a percentage of GDP, standing at roughly 0.5% in 2016 and 2017, substantially below the EU average of just over 2%. The country joined the European Space Agency (ESA) in 2011, and CERN in 2016. In 2018, however, Romania lost its voting rights in the ESA due to a failure to pay €56.8 million in membership contributions to the agency.