This is actually pretty interesting if you can be bothered reading it.
https://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwiqst-D3_6BAxWms1YBHYdrCis4ChAWegQIBhAB&url=https%3A%2F%2Fsanaacenter.org%2Fpublications%2Fmain-publications%2F20682&usg=AOvVaw2kC8gmUoxzOhl95NkIZj83&opi=89978449