The study looked at how government spending affects the economy in the United States, especially when interest rates are very low. They found that when interest rates are near zero, government spending has a bigger impact on the economy, with multipliers ranging from 3.4 to 3.7. When interest rates are higher, the impact is smaller, with multipliers ranging from 1.5 to 2.7. This suggests that government spending is more effective in boosting the economy when interest rates are low.