There were a number of factors behind this impressive economic performance, but time and space limit me to mentioning only the main ones. The four most important, I believe, are as follows: (i) There was a big gap to be made up following the Depression and the Second World War.
The 1950s and 1960s was a period of post-war reconstruction or “catch-up” for most countries. The largest growth pick-up occurred in the countries most devastated by the war, such as Germany, Italy, Japan and Austria, and the least pronounced (although still significant) were in the United States, Canada, Switzerland, Sweden and Australia.