Replace the question mark with a number

A man and his wife have gone to bed. After laying in bed for a few minutes the man cuts a fart. His wife rolls over and asks, "What in the world was that?"
The man says, "Touchdown, I'm ahead, seven to nothing."
A few minutes later the wife lets one loose. The man says to her, "What was that?"
She replies, "Touchdown, tie score."
The man lays there for about ten minutes trying to work one up. He tries so hard that he shits all over the bed.
The wife asks, "Now what in the world was that?" He replies, "Half time. Switch sides."