In the year 2009 the tendency towards reducing total number of operating nuclear power units continued. But the decline is about to come to an end – for the first time since 2007 new power units have been connected to the network, and the number of units under construction has exceeded 50. According to the IAEA official data, by 1 January 2010 there had been 437 nuclear power reactors with total capacity of about 370.2 GVtel, operated over the world.