<Tr> <Td> Kaushik Basu </Td> <Td> 2012--2016 </Td> <Td> India </Td> </Tr> <Tr> <Td> Paul Romer </Td> <Td> 2016--2018 </Td> <Td> United States </Td> </Tr> <P> The International Bank for Reconstruction and Development (IBRD) has 189 member countries, while the International Development Association (IDA) has 173 members . Each member state of IBRD should be also a member of the International Monetary Fund (IMF) and only members of IBRD are allowed to join other institutions within the Bank (such as IDA). </P> <P> In 2010 voting powers at the World Bank were revised to increase the voice of developing countries, notably China . The countries with most voting power are now the United States (15.85%), Japan (6.84%), China (4.42%), Germany (4.00%), the United Kingdom (3.75%), France (3.75%), India (2.91%), Russia (2.77%), Saudi Arabia (2.77%) and Italy (2.64%). Under the changes, known as' Voice Reform--Phase 2', countries other than China that saw significant gains included South Korea, Turkey, Mexico, Singapore, Greece, Brazil, India, and Spain . Most developed countries' voting power was reduced, along with a few developing countries such as Nigeria . The voting powers of the United States, Russia and Saudi Arabia were unchanged . </P>

How many countries are the members of world bank
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