What were the causes of Brtain 's population doubling every 50 years ?
Population growth was steepest in the period after World War II ( 1.4 % per annum during 1950-1970 , doubling time 50 years ) , it slowed down during the 1970s to 1980s and has since again picked up to 1 % during the 2000s ( doubling time 70 years ) .