Flow of Money Diagram Illustrating the Investment Multiplier Effect with MPC vs. Multiplier Graph By Edward Matulanya  Explore the concept of the investment multiplier, its formula, real-world examples, sectoral analyses, and policy implications to understand how investment drives economic growth. Introduction John Maynard Keynes (1936) introduced the investment multiplier to explain how an initial increase in spending produces a multiplied effect on national income. The concept underpins fiscal policy, economic recovery strategies, and private sector investment planning (Samuelson & Nordhaus, 2010). Understanding the multiplier allows policymakers to predict the broader economic impact of investments, guiding strategies to maximize employment, income, and GDP growth. 1. Meaning of Investment Multiplier The investment multiplier measures how an initial change in investment leads to a larger change in total economic output. Keynes (1936) posited that spending creates inco...