Check the link in Post 10. It says 2,400 calories per person per day on average. So, the 100 calories per serving (suggested in post 5) on 36,000 servings would be correct.
36,000 servings times 100 calories per = 3,600,000 calories.
3,600,000 / 365 days = 9,863 calories/day.
9,863 calories / 4 people = 2,465 calories per day per person. So they are considering a serving as 100 calories.
Sorry, the link says 2,000 calories per day on average (based on four people), not 2,465. My numbers come out to 2,465 per day per person based on 4 people for one year.