For the first time since the Black Death in the 1300s, the world’s population will fall. According to a study in the Lancet medical journal, each woman would have to have 2.1 children on average to maintain the current population. In the UK, it’s currently 1.49. The Lancet notes that the falling population will affect social services and more. The situation will be very noticeable by 2100. The paper notes that the shift in population will change the global economy and seats of power. The Republic of Congo will become a player, as it currently has a fertility rate of 6.99. About 50-million people died in the Black Death with Europe losing half its population.