A season without laughs is a dreadful one indeed. Prior to uncovering this rare jewel of ratings, the 1973-74 and 2009-10 Historic Sitcom Scorecard delivered a shiver of sparse sitcoms. This season managed to not only surpass this ice of laughter, but also stab a chisel into America's most durable franchise and deliver an icy-hot blow of 20 sitcoms. Even a sitcom which wrangled 5th Place like Bridget Loves Bernie bit the dust!
This, along with other diverse entries of ratings data can be found in the TVRG Ratings Library, located at the following link: http://www.tvratingsguide.com/2018/01/tvrg-ratings-library.html
It would appear NBC won the sitcom average by a landslide. However, that was by default of the one and only sitcom Sanford and Son. Truth be frozen, CBS again cleaned house with socially relevant wins from All in the Family, Mary Tyler Moore and Maude. ABC deflected this trend with simpler laughs from The Brady Bunch, The Odd Couple and Room 222. Be grateful other seasons bostered healthier rosters, as the 1972-73 season was harsh at best for television laughs.
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