Some statistics in Yahoo! Fantasy Baseball are derived from applying a mathematical formula to multiple statistical categories. The following formulas are used to calculate composite stats for both individual players and fantasy teams.

Composite stats for your team are derived by the active players on your roster only. You do NOT receive credit for stats earned by reserves or those stats earned by players prior to their acquisition.

BATTERS:

Batting Average (AVG) = Hits / At Bats

Slugging Percentage (SLG) = Total Bases / At Bats

On-Base Percentage (OBP) = (Hits + Walks + Hit By Pitch) / (At Bats + Walks + Hit By Pitch + Sacrifice Flys)

Total Bases (TB) = Hits + Doubles + (Triples * 2) + (Home Runs * 3)

On-base + Slugging Percentage (OPS) = On-Base Percentage + Slugging Percentage

Net Stolen Bases (NSB) = Stolen Bases - Caught Stealing

Stolen Base Percentage (SB%) = 100 * Stolen Bases / (Stolen Bases + Caught Stealing)

Fielding Percentage (FPCT) = (Putouts + Assists) / (Putouts + Assists + Errors)

PITCHERS:

Earned Run Average (ERA) = (Earned Runs * 9) / Innings Pitched

WHIP Ratio (WHIP) = (Walks + Hits) / Innings Pitched

Strikeouts per Nine Innings (K/9) = (Strikeouts / Innings Pitched) * 9

Strikeout to Walk Ratio (K/BB) = Strikeouts / Walks

On-Base Percentage Against (OBPA) = (Hits Allowed + Walks + Hit Batters) / Total Batters Faced

Winning Percentage (WIN%) = Wins / (Wins + Losses)

Hits Per Nine Innings (H/9) = (Hits * 27) / Outs

Walks Per Nine Innings (BB/9) = (Walks * 27) / Outs

Save Percentage (SV%) = Saves / Save Opportunities

Net Saves (NSV) = Saves - Blown Saves

These formulas are the official formulas used to calculate real-life stats. Yahoo! Sports does not change these formulas in any way.