Forms of spending which do not derive from current income. These are investment spending by firms, government spending, and export sales to foreigners. If injections exceed leakages from the circular flow of incomes, the income level starts to rise.

• import deposit
• Import Duties Act, 1932
• import duty
• imported inflation
• import levy
• import licence
• import penetration
• import propensity
• import quota
• import restriction
• imports
• import substitution
• import surcharge
• import tariff
• imputation system
• imputed charge for consumption of non-trading capital
• imputed income
• IMRO
• incentive-compatibility
• incentives
• incidence of taxation
• income
• income approach to GDP
• income change, compensating
• income distribution