US Finance Glossary

Plain-English definitions for terms used on Beforeview.

AGI(Adjusted Gross Income): Gross income minus specific deductions like contributions to a traditional IRA or student loan interest. Used as the starting point for most US tax calculations.
ARM(Adjustable-Rate Mortgage): A mortgage where the interest rate changes periodically based on a published index. Contrasts with a fixed-rate mortgage.
CAGR(Compound Annual Growth Rate): Geometric mean annual growth rate over a period. Formula: (end / start)^(1/years) − 1. Used on our inflation pages to show the annualized rate.
CCPA / CPRA(California Consumer Privacy Act / Rights Act): California state laws giving residents rights over personal data businesses collect about them.
CPI-U(Consumer Price Index for All Urban Consumers): BLS series CUUR0000SA0. The most widely used US inflation measure. Annual averages of monthly CPI-U readings.
Effective tax rate: Total tax paid divided by gross income. Different from the marginal rate (the rate on your last dollar earned).
FICA(Federal Insurance Contributions Act): Payroll tax that funds Social Security (6.2% up to a wage base) and Medicare (1.45%, with an additional 0.9% above a threshold).
FLSA(Fair Labor Standards Act): US federal law setting minimum wage, overtime pay (1.5× regular rate over 40 hrs/week), and recordkeeping requirements for non-exempt employees.
FMR(Fair Market Rent): HUD's annual estimate of the cost of rent for a private market unit by metro area. Used for federal housing program calculations.
GDPR(General Data Protection Regulation): EU/UK privacy law giving residents rights over personal data collected by websites and businesses.
HOH(Head of Household): Tax filing status for unmarried taxpayers paying more than half the cost of keeping up a home for a qualifying person. Generally lower tax than Single.
Marginal tax rate: The tax rate that applies to your last dollar of taxable income. The US has progressive brackets, so different portions of income face different rates.
MFJ(Married Filing Jointly): Tax filing status for married couples reporting combined income on one return. Usually the most tax-efficient status for couples.
MFS(Married Filing Separately): Tax filing status for married people filing separate returns. Rarely tax-optimal but used in some situations (e.g., student loan repayment plans).
Medicare additional tax: Extra 0.9% Medicare tax on wages over $200,000 (Single) or $250,000 (MFJ). Added by the Affordable Care Act.
P&I(Principal and Interest): The portion of a mortgage payment that goes to repaying the loan principal plus interest. Excludes property tax, insurance, HOA and PMI.
PMI(Private Mortgage Insurance): Insurance lenders require when down payment is less than 20% of home value. Typically 0.5%–1.5% of loan annually.
Powerball / Power Play: US multi-state lottery with 5 white balls (1–69) and a Powerball (1–26). Power Play is an optional multiplier on non-jackpot prizes.
Mega Millions / Megaplier: US multi-state lottery with 5 white balls (1–70) and a Mega Ball (1–25). Megaplier is the optional multiplier (up to 5×) on non-jackpot prizes.
Quintile: One of five equal parts of a distribution. The 1st quintile is the lowest 20% of incomes, the 5th is the top 20%.
Real vs nominal: Nominal = the face dollar amount in a given year. Real = adjusted for inflation, expressed in dollars of a reference year.
Social Security wage base: The maximum amount of earnings subject to Social Security tax. In 2025: $176,100.
Standard deduction: Fixed dollar amount you can subtract from your AGI before applying tax brackets, instead of itemizing. In 2025: $15,000 Single, $30,000 MFJ.