I have a question about some research I'm trying to conduct. There is a training program implemented by the airlines in the 1980's that claims to help lower aircraft accidents called Crew Resource Management. I'm comparing the airline accidents and incidents in the 1970's to those in the 1990's to see if they went down in the 90's and determine if this Crew Resource Management training was helpful. How would I set this up to run a Chi-square test of independence to look at the association of this? Please give me a step by step breakdown of how I would would go about conducting this chi-square test.