original_query: What is the formula for calculating the combined percentage overround for accumulator bets?
query: What is the formula for calculating the combined percentage overround for accumulator bets?
answer: The combined percentage overround (OD) for an accumulator bet with individual books B1, B2,...Bi (expressed as decimals) is calculated as: OD = B1 × B2 × ... × Bi × 100 − 100