Economic impact of violence

The Economic Value of Peace: e.g. ‘The total economic impact of violence to the world economy in 2015 was estimated to be $13.6 trillion and is expressed in purchasing power parity (PPP) terms. This is equivalent to 13.3 per cent of world GDP or $1,876 PPP per annum, per person.’ From 
http://oxfamblogs.org/fp2p/a-philanthropist-using-systems-thinking-to-build-peace/