When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
You are correct, they have always made more auto's than manauls. However, the only recent year that they only made auto's was in 1982. Other than that they made only auto's in 1953, 54, maybe 55. I'm not sure when they introduced the first manual (my vette trivia is starting to go south, I need to fix that), but it has been an option ever since, except 82 of course.
You might count 83 , being that there is only 1 proven to exist, I'm pretty sure it's an auto, but I could easily be mistaken. I didn't pay that much attention to it when I was at the museum.
My blackbook is at home also, but I remember approx 5-10 autos for every manual in the 80's and 90's (except no manual in '82 and no car in '83). In the late 60's and into early 70's that ratio was reversed most of those years to 2-10 manuals for every auto (I believe a year or two were even-up), and there were close-ratio and wide-ratio manuals to choose from.