To make a graph of the Win Expectancy of a baseball game, use the graph a game tool.
This data is from MLB games from 1957-2015, including postseason games. All data is available at Retrosheet.
Linked from: FiveThirtyEight (search for "eighth inning"), The Washington Post, CBS Sports, Royals Review, Beyond the Box Score, and more!
Idea taken from Win Expectancy Finder at walkoffbalk.com. Here's a good article about Win Expectancy. Leverage Index calculations based on this article.
The information used here was obtained free of charge from and is copyrighted by Retrosheet. Interested parties may contact Retrosheet at 20 Sunset Rd., Newark, DE 19711.
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