Financial Glossary

The process of paying off a loan through regular payments over time. Each payment covers interest first, then reduces the principal balance. Early payments are mostly interest; later payments are mostly principal.

The yearly cost of borrowing money, including interest and fees, expressed as a percentage. Unlike a simple interest rate, APR provides a more complete picture of the true cost of a loan.

A series of equal payments made at regular intervals over time. Examples: monthly mortgage payments (you pay), or pension income (you receive). An ordinary annuity pays at period end; an annuity due pays at period start.

The division of an investment portfolio among different asset categories — stocks, bonds, real estate, cash. Determines most of the portfolio's risk and return characteristics. Generally: more stocks = higher risk/return; more bonds = lower risk/return.

A debt instrument where an investor lends money to a borrower (government or corporation) for a defined period at a fixed or variable interest rate (coupon). Bonds are generally lower risk than stocks but offer lower returns.

A financial plan that estimates income and expenses over a period. The 50/30/20 rule: 50% needs, 30% wants, 20% savings. A budget is the foundation of any personal finance plan.

Compound Annual Growth Rate — the rate at which an investment would have grown if it grew at a steady annual rate. CAGR = (Final Value / Initial Value)^(1/years) − 1. Used to compare investments over different time periods.

The profit from selling an asset for more than you paid. Short-term (held <1 year): taxed as ordinary income. Long-term (held >1 year): taxed at preferential capital gains rates (0%, 15%, or 20% in the US).

A savings product offered by banks with a fixed interest rate for a specified term (3 months to 5 years). Higher rate than savings accounts; early withdrawal penalties apply. FDIC-insured up to $250,000.

Interest calculated on both the initial principal and all previously accumulated interest. The formula: FV = PV × (1+r)^n. Over long periods, compounding creates exponential growth — this is why starting to invest early has such a dramatic effect.

A numerical representation (300–850 in the US) of your creditworthiness. Calculated from payment history (35%), amounts owed (30%), length of credit history (15%), new credit (10%), and credit mix (10%). 700+ is good; 750+ is excellent.

Dollar-Cost Averaging — investing a fixed amount at regular intervals regardless of market price. You buy more shares when prices are low and fewer when high, reducing the impact of volatility. DCA removes the temptation to time the market.

A debt payoff strategy where you pay the minimum on all debts except the one with the highest interest rate, which gets all extra payment. Mathematically optimal — saves the most interest.

A debt payoff strategy where you pay the minimum on all debts except the smallest balance, which gets all extra payment. After paying off one debt, roll that payment to the next. Psychologically motivating — provides quick wins.

A decrease in the general price level of goods and services. The opposite of inflation. While it sounds good, deflation often signals economic distress — consumers delay purchases expecting lower prices, slowing the economy.

The decrease in value of an asset over time. Cars typically depreciate 15–20%/year. Real estate can appreciate (or depreciate). Depreciation is also an accounting concept for allocating asset cost over its useful life.

Spreading investments across different assets, sectors, and geographies to reduce risk. If one investment drops, others may rise. A portfolio of 30+ uncorrelated stocks has dramatically lower volatility than a single stock.

A distribution of a company's profits to shareholders. Yield = annual dividend / share price. Qualified dividends (US stocks, held >60 days) are taxed at capital gains rates. DRIP = Dividend Reinvestment Plan.

See DCA above.

Effective Annual Rate — the actual annual return (or cost) after accounting for compounding. EAR = (1 + APR/n)^n − 1, where n is compounding periods per year. A 12% APR compounded monthly = 12.68% EAR.

3–6 months of essential living expenses held in a liquid, low-risk account (high-yield savings or money market). Protects against job loss, medical emergencies, or unexpected expenses without going into debt.

Exchange-Traded Fund — a basket of securities (stocks, bonds, commodities) that trades on an exchange like a stock. Lower fees than mutual funds; highly diversified; tax-efficient. S&P 500 ETFs (e.g., VTI, SPY) track the 500 largest US companies.

The annual fee charged by mutual funds and ETFs, expressed as a % of assets. An index fund with 0.03% ER costs $3/year per $10,000. Actively managed funds average 0.5–1.5%. Over 30 years, a 1% vs 0.05% difference costs tens of thousands in wealth.

Financial Independence, Retire Early — a lifestyle movement. The FIRE number = annual expenses / Safe Withdrawal Rate (typically 4%). A person spending $50,000/year needs $1,250,000 (at 4% SWR) to retire. Variants: Lean FIRE, Fat FIRE, Coast FIRE.

Relates nominal returns, real returns, and inflation: (1 + real) = (1 + nominal) / (1 + inflation). Simplified: real ≈ nominal − inflation. Essential for understanding what your investment actually gains in purchasing power.

Gross: total income before taxes and deductions. Net: take-home pay after all deductions. For investment calculations, use net income as that's the money actually available to spend or invest.

An investment made to reduce the risk of adverse price movements in another asset. Common hedges: owning bonds to offset stock risk, buying put options on a stock position, holding gold as an inflation hedge.

A fund designed to replicate the performance of a market index (S&P 500, FTSE 100, etc.). Passively managed; very low expense ratios. Evidence strongly supports index investing outperforms most active managers over long periods.

The rate at which the general price level rises over time, reducing purchasing power. Measured by CPI (Consumer Price Index). US historical average: ~3%/yr. At 3% inflation, $100 today buys only $74 in 10 years.

The percentage of principal charged or paid for the use of money over a period. The nominal rate is stated; the effective rate (EAR) accounts for compounding. The real rate = nominal rate − inflation.

Internal Rate of Return — the discount rate that makes the net present value of all cash flows equal to zero. Used to compare investment projects. If IRR > your required return (hurdle rate), the investment adds value.

How quickly an asset can be converted to cash without significantly affecting its price. Cash = perfectly liquid. Real estate = illiquid. Financial planning rule: always maintain some liquid emergency fund; illiquid investments offer higher returns as compensation.

The sum of all future cash flows discounted to present value, minus the initial investment. NPV > 0 means the investment creates value at the discount rate. NPV = Σ[CF_t / (1+r)^t] − Initial Investment.

Total assets minus total liabilities. The most comprehensive single measure of financial health. Positive = you own more than you owe. Growing net worth over time is the goal of personal finance.

Nominal: a value not adjusted for inflation. Real: inflation-adjusted. "The S&P 500 returned 10% nominally and 7% in real terms" means: after 3% inflation, your purchasing power only grew 7%. Always compare investments in real terms.

The value of the best alternative forgone when making a decision. If you use $10,000 to buy a car instead of investing it at 7%, the opportunity cost is $10,000 × 7% = $700/year. Every financial decision has an opportunity cost.

A collection of investments held by an individual or institution. A diversified portfolio typically includes stocks, bonds, and possibly real estate or other assets. Asset allocation determines the portfolio's expected risk and return.

The current value of money to be received in the future, discounted at a given rate. PV = FV / (1+r)^n. $10,000 in 10 years at 8%/yr = $4,632 PV. Useful for comparing investments with cash flows at different times.

The original amount of a loan or investment, before interest. In a mortgage, your principal is the purchase price minus down payment. As you make payments, the principal decreases (amortization).

Investment return after adjusting for inflation and taxes. Fisher equation: (1 + real) = (1 + net nominal) / (1 + inflation) − 1. A savings account at 4% with 3% inflation and 20% tax: net nominal = 3.2%, real return = 0.19%. Often negligible for low-yield assets.

Periodically adjusting your portfolio back to target asset allocation. Example: if stocks rise to 70% of your target-60% portfolio, sell some stocks and buy bonds. Rebalancing enforces buy-low/sell-high discipline and controls risk.

(Gain − Cost) / Cost × 100. A simple measure of investment profitability. Doesn't account for time, making CAGR more useful for multi-year comparisons. "50% ROI over 5 years" vs "8.4% CAGR" — the CAGR is more meaningful.

The theoretical return of an investment with zero risk. In practice, US Treasury bills are used as the risk-free benchmark. The excess return above risk-free rate = risk premium. Investors must be compensated for taking on additional risk.

A quick way to estimate doubling time: 72 ÷ annual interest rate = years to double. At 8%, money doubles in 72/8 = 9 years. The exact formula is ln(2)/ln(1+r). Rule of 114 = triple time; Rule of 144 = quadruple time.

Standard & Poor's 500 Index — a market-cap-weighted index of 500 large US companies. The most widely followed US stock market benchmark. Historical average return: ~10% nominal, ~7% real per year since 1926. The baseline for US investing performance.

In retirement planning, the percentage of portfolio you can withdraw annually without running out of money. The classic "4% rule" (Trinity Study) suggests 4% is safe for a 30-year retirement with a 60/40 portfolio. At 3.3% SWR you plan for 50 years.

A share of ownership in a company. Stocks (equities) offer potentially higher returns than bonds but with higher volatility. Over 20+ year periods, diversified stocks have historically beaten all other asset classes, compensating for their volatility risk.

Money already spent that cannot be recovered. Should not influence future decisions — only future costs and benefits matter. Staying in a bad investment because you've already lost money on it is the "sunk cost fallacy."

See Safe Withdrawal Rate above.

Investment accounts with special tax treatment: Traditional IRA/401k = tax deduction now, taxed on withdrawal; Roth IRA/401k = no deduction now, tax-free withdrawals. Max contributions: 401k $23,500/yr (2025), IRA $7,000/yr (2025).

The fundamental principle that money available today is worth more than the same amount in the future, because it can be invested and earn returns. All financial calculations (loans, bonds, retirement) rely on TVM.

The degree of variation in an investment's returns over time. Measured by standard deviation. High volatility = large price swings; low volatility = stable returns. Volatility is not the same as risk — volatility is temporary; permanent loss of capital is risk.

The income return on an investment, expressed as a percentage of cost or current value. Dividend yield = annual dividend / price. Bond yield = coupon / price. Yield on cost = current annual dividend / original purchase price.