**Number of (Singes+[2xDoubles]+[3xTriples]+[4xHome Runs]) divided by At-Bats.**Slugging percentage, or slugging average, is defined as total bases per at-bat. To calculate a player’s total bases you award a 1 for a singe, 2 for a double, 3 for a triple and 4 for a home run. Then you add them all together. Divide that total by number of At-Bats.
Below is an example:
Nolan has 75 At Bats. He has 23 singles, 12 doubles, 3 triples and 5 home runs. His Slugging Average is: 1.013
This means that he average one base for every at bat. That is pretty darn good!