I know many on here are sick of talking about this 52 year old ruling for radio, and so am I.  However on Jerry Agar's show one of the topics on Friday was about cancon in the movie industry and Jerry went on a bit of a rant about CKLW.

He said again (and wrongly) that it was cancon that took CKLW from being the most dominate radio station in North America to putting them out of business. 

A bit of an exaggeration and not true.  Jerry made it sound like the moment LW started to play cancon that the station's ratings tanked.  CKLW was the dominate station in Detroit and a few other cities like Toledo for years after cancon was brought in 1971.

In fact one year after the introduction of the regulation by the CRTC, CKLW ratings had gone up 20% and the station enjoyed their best numbers for years after 1971. 

Similar to many US AM top 40 stations it was FM that started the ratings to slide in the late 70's and early 80's.  CKLW's softening in popularity was due mostly to listeners switching to FM and also the fact that the station was beginning to sound somewhat dated in their approach. 

Many of the big AM top 40 stations in America had the same shift in listeners.  WLS, WABC, WNBC, KHJ,  WKBW, KFRC and many others were all overwhelmed by FM at the same time as CKLW.  Since the same thing happened to these stations, it clearly wasn't cancon that put LW "out of business."  Besides CKLW AM lives on today as the number one station in Windsor and Essex county.