Research director Håvard Mokleiv Nygård suggested the Korean War in the early 1950s may have been a 'breaking point' signalling a change in the number of people killed in battle.
'The wars after the Korean War (1950–1953) have killed a quarter as many people as the wars before the Korean War,' he said.
'The change after this breaking point is an indication that the world has become a more peaceful place,' adding Nygård, whose researchers work alongside statisticians at the University of Oslo.
Nygård said 'extensive use of statistics' was used by the institute, which aims to find out why war happens, how war develops and what steps can be taken to halt conflicts.
He added: 'The distribution of the number of people dying in war does not follow any normally distributed curve. There are many wars in the middle of the curve with a certain number of killed and few wars on the curve's extremes, with few or many killed.