Life-cycle finance is a consumption-smoothing problem across time. You must capture income during your high-productivity years and distribute it across a lifespan of unknown duration. The challenge is compounded by inflation and market risk. Saving cash is a guaranteed loss in real terms; investing it exposes you to volatility. Furthermore, you face mortality risk — the planning mismatch of outliving your assets once your capacity to sell labor has dropped to zero.
Your labor income has its own risk profile. A tenured professor has a bond-like income; a commission-only real estate broker has an equity-like income. A rational asset allocation treats your human capital as an asset on your consolidated balance sheet and balances your financial portfolio accordingly. A diversified asset mix offsets these structural exposures, ensuring your total economic position remains robust against sector-specific shocks.
As you age, the present value of your future wages approaches zero. Your financial capital must scale to replace it.
This shift dictates your investment timeline. Early in your career, with forty years of labor income ahead and negligible financial savings, you can easily tolerate high volatility. A heavy allocation to equities is mathematically sound. As your career winds down, your financial portfolio must assume the role of the income generator. You must transition from wealth accumulation to capital preservation, shifting toward less volatile, income-producing assets like bonds and structured fixed income instruments to protect your spending floor.