As a result of this calamity, the population of Ireland decreased by 25%, or 2 million people, in the 1840s
It is sometimes referred to, 
mostly outside Ireland, as the Irish Potato Famine, because about two-fifths of the 
population was ... During the famine, approximately one million people died and 
a million more... [DOC] [TLE] Irish population analysis - Wikipedia [PAR] The population of the Island of Ireland in 2012 was approximately 6.4 million 
comprising 4.58 million in the Republic of Ireland with another 1.8 million in 
Northern Ireland.