Cat owners are statistically more likely to have a college degree than dog owners. In fact, households with at least one degree-holder are about 1.5 times more likely to own a cat than a dog. Despite the education level of their owners, dogs are actually better at reasoning than cats, according to some tests.
More facts about cats and dogs:
I'm a widow (2008) and I have always had a cat. I also had poodles when I was married. I recently received an American/English Bulldog puppy. I kept him for about nine months (112 lbs vs. 62 pounds and still growing); he was very smart but too much for me to handle and afford.
When I finally gave him to a new family, my stress was reduced, my cat's much happier and so is my back. I was constantly house-proofing and picking up bits and pieces of things I thought were out of his reach.
I wasn't involved in the research of facts, but cats certainly fit me and my lifestyle!