Estimate the annual US market for dog food.

The approach is the number of dogs in the country times what each costs to feed per day. There are about 130 million households in the US. I'll say 45% have a dog, which is 58.5 million, and I'll round to 60 million. Among people I know it's a bit under half, and it's lower in big cities. Most owners have one dog and a good share have two or more, so at 1.5 dogs each that's 90 million dogs. A typical dog eats about a pound of dry food a day, and a mid-price bag works out to about $1.50 a pound, so $1.50 a day. 90 million times $1.50 is $135 million a day. Times 365 is about $49 billion a year. That seems like a reasonable size for this market to me.

I'll size this at store prices and count food only, not treats. The approach is the number of dogs, split by size because a big dog eats several times what a small one does, times what each costs to feed per day. There are about 130 million households in the US. I'll say 45% have a dog, which is 58.5 million, and I'll round to 60 million. Among people I know it's a bit under half, and it's lower in big cities. Most owners have one dog and a good share have two or more, so at 1.5 dogs each that's 90 million dogs. I'll put 40 million of them as small, 30 million as medium and 20 million as large. A medium dog eats about a pound of dry food a day, and a mid-price bag works out to about $1.50 a pound, so $1.50 a day. A small dog eats about half that, so 75 cents. A large dog eats half as much again, so $2.25. That's $30 million a day for small dogs, $45 million for medium and $45 million for large, which is $120 million a day. Times 365 is about $44 billion a year. As a check from outside these inputs, $120 million over 90 million dogs is about $1.30 a dog a day. A person's groceries run about $6 a day, so a dog costs a bit under a quarter of a person, which fits a smaller animal eating cheaper food. The number I trust least is the $1.50 a pound. Budget brands cost about half that, and fresh or prescription food costs several times more. I'd give a range of $35 to $55 billion. What manufacturers receive is lower, since stores keep a margin.