How many boxes of macaroni and cheese were eaten in the United States last year?

"In knowing that the population in the United States is around 325 million people, my biggest factors in determining my answer will be that children between the ages of two and ten consume 75% of the mac and cheese each year and that the other 25% is consumed by ages ten and above. The other factor is that the kids eat one box per week and the ages over ten eat two per month. So, I'll determine that there are 80 million children between two and ten and figure that they'll eat 4.2 billion boxes. Then I'll determine that 240 million people over ten eat two per month to get 5.7 billion boxes of mac n' cheese. When added together, I'd say the final answer is right around 10 billion boxes of man n' cheese are eaten in the US each year."