A $500 million increase in government purchases of goods and services directly increases aggregate spending by $500 million, which then starts the multiplier in motion. It will increase real GDP by $500 million × 1/(1 − MPC). A $500 million increase in government transfers increases aggregate spending only to the extent that it leads to an increase in consumer spending. Consumer spending rises by MPC × $1 for every $1 increase in disposable income, where MPC is less than 1. So a $500 million increase in government transfers will cause a rise in real GDP only MPC times as much as a $500 million increase in government purchases of goods and services. It will increase real GDP by $500 million × MPC/(1 − MPC).