Goat ball spread

Challenge
No

Cthulhu is thinking about betting on goat ball point spreads. It wants you to figure out some statistics.

Point spread is the difference between scores in a game. So if:

  • The New York Nannies scored 10 points and the Buffalo Billies scored 7, the spread would be 3 for the game.
  • The Brisbane Bed Bugs scored 11 points and the Yosemite Yolks scores 16, the spread would be 5.
  • The average of the spreads for the games would be (3+5)/2 = 4.

You can download the start workbook with the data. It looks like this:

Start

The scores should all be numbers that are zero or more. There are data errors.

Write a program to compute the two counts and the mean, as well as the score differences. Here's the output:

Output

Differences are always positive, or zero.

You can assume that at least some of the data is valid.

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