These multipliers are calculated for individual sectors within an economy based on national input-output tables, which quantify how sectors produce goods/services and trade with each other. We then can use the multipliers to calculate the total economic impact of the project or activity, as the multiplier tells us how much an increase in one sector's output impacts all other sectors: direct effects include the purchase of goods and services by the sector itself, indirect effects capture spillover effects along the sector supply chain and induced effects capture the impact of increased household consumption.