Critically discuss the theoretical argument and practical implication of CAPM.

“The Capital Asset Pricing Model (CAPM)’ has dominated academic literature and greatly influenced the practical world of finance and business for almost half a century; as a way to measure systematic risk. Researchers in the 1980s and 1990s have questioned the relationship between systematic risk, measure beta, and returns on securities. Despite heavy criticism of the model from the academic community, CAPM has reached new heights of popularity in the outside world (Arnold pp 269). Hundreds of thousands have studied the CAPM in universities and now hold key positions ready to make decisions based on the model.” 

A 1000 word count report on CAPM using word and a minimum of 5 references from web, book, etc using harvard APA referencing.