Why $1,000 Today Is Worth More Than $1,000 Next Year (Time Value of Money)

The principle that money available today is worth more than the same amount in the future, because money can earn returns when invested. A dollar today invested at 7% annual return is worth $1.07 in a year. In 10 years, it's worth $1.97. The 'present value' of a future amount is what that future amount is worth in today's dollars, after accounting for what returns you could have earned in the meantime. This concept underlies loan calculations, investment valuations, retirement planning, and any financial decision involving money at different points in time.

Future value is what a sum of money will grow to over time at a given interest rate. $5,000 at 8% for 10 years has a future value of $5,000 × (1.08)^10 = $10,795. Present value is the reverse: what is a future sum worth in today's dollars? If you'll receive $10,795 in 10 years and your discount rate is 8%, the present value is $10,795 ÷ (1.08)^10 = $5,000. You're 'discounting' the future sum back to the present. Both calculations use the same formula, just solving for different variables.

Inflation reduces purchasing power over time, which reinforces the time value of money concept. If inflation runs at 3% annually, $1,000 next year buys only what $970 buys today. This creates two layers to the time preference for today's money: first, you could invest it and earn returns; second, if you don't invest it, inflation erodes its purchasing power. Real returns (investment returns minus inflation) represent the true increase in purchasing power. A 7% nominal investment return at 3% inflation = approximately 4% real return in purchasing power.