Glossary: Portfolio Construction Terms

This glossary defines 28 essential terms for building and managing diversified portfolios. Each entry provides a one-sentence definition with quantified thresholds, historical data, or concrete examples. Portfolio construction principles are grounded in Modern Portfolio Theory (Markowitz, 1952) and factor research (Fama & French, 2015).

Terms

Asset Allocation

The division of a portfolio across asset classes (stocks, bonds, cash, real estate) based on goals, risk tolerance, and time horizon; 60/40 (60% stocks, 40% bonds) is a common balanced allocation.

Benchmark

A standard index (S&P 500, 60/40 portfolio) against which portfolio performance is measured to assess whether active decisions add or destroy value.

Core-Satellite

Portfolio strategy combining passive core holdings (80-90% in broad index funds like VTI) with active satellite positions (10-20% in sector tilts or factor funds).

Diversification

Spreading investments across multiple assets, sectors, or geographies to reduce single-position risk; a 3-fund portfolio (US stocks, international stocks, bonds) is diversified.

Dollar-Cost Averaging (DCA)

Investing fixed dollar amounts at regular intervals (monthly, quarterly) regardless of price, reducing timing risk and emotional decision-making.

Drift

When asset allocation deviates from target due to market movements (stocks rally from 60% to 70% of portfolio), requiring rebalancing.

Drawdown

Peak-to-trough decline in portfolio value during a loss period; maximum drawdown measures worst loss experienced (e.g., -22% in 2022 bear market).

Equity

Ownership stake in a company via stocks; equities provide growth potential but higher volatility than bonds (15% annual standard deviation versus 3.5% for bonds).

Expense Ratio

Annual fee charged by mutual funds or ETFs as percentage of assets; VTI charges 0.03%, actively managed funds average 0.75%-1.5%.

Factor Investing

Tilting portfolio toward stocks with specific characteristics (value, quality, momentum) that historically outperform; value factor returned 4.8% annually over growth (1927-2023).

Fixed Income

Bonds and other debt securities that pay regular interest; fixed income provides stability and income, lower volatility than stocks.

Glide Path

Automatic asset allocation shift in target-date funds, moving from stocks to bonds as retirement approaches (e.g., 90% stocks at age 30 → 40% stocks at age 65).

Index Fund

Mutual fund or ETF tracking a market index (S&P 500, total stock market) via passive replication; 89% of active funds underperform index funds over 15 years.

Market-Cap Weighting

Index methodology weighting stocks by market capitalization (price × shares outstanding); Apple at $3 trillion gets larger weight than smaller companies.

Modern Portfolio Theory (MPT)

Framework developed by Harry Markowitz (1952) showing diversification reduces risk without sacrificing expected return by combining uncorrelated assets.

Passive Investing

Buy-and-hold strategy using index funds, minimizing trading and fees; passive investors accept market returns rather than attempting to beat the market.

Position Limit

Maximum allocation to single stock or sector (e.g., no more than 5% in any one stock, 20% in any sector) to prevent concentrated risk.

Rebalancing

Selling outperforming assets and buying underperformers to restore target allocation; rebalance when asset drifts >5 percentage points or annually.

Risk Budgeting

Allocating portfolio risk (volatility) across assets to achieve desired risk level; 60/40 portfolio budgets 85% of risk to stocks, 15% to bonds despite 40% bond allocation.

Risk Tolerance

Maximum portfolio loss an investor can endure without panic-selling; measured by willingness to hold during -20% to -50% drawdowns.

Sector Rotation

Tactical strategy shifting between economic sectors (technology, healthcare, energy) based on business cycle; 87% of sector rotation strategies fail to beat market (Vanguard, 2022).

Sharpe Ratio

Risk-adjusted return metric: (Portfolio Return - Risk-Free Rate) / Volatility; Sharpe >1.0 is excellent, 0.5-1.0 good, <0.5 poor.

Target-Date Fund

All-in-one fund automatically adjusting allocation from stocks to bonds as target retirement date approaches; Vanguard Target Retirement 2050 holds 90% stocks, shifting to 40% by 2050.

Tax-Loss Harvesting

Selling investments at a loss to offset capital gains taxes, reducing tax liability while maintaining market exposure via similar replacement securities.

Three-Fund Portfolio

Simplified diversified portfolio: US stocks (VTI), international stocks (VXUS), bonds (BND); covers global equities and fixed income with three holdings.

Tracking Error

Volatility of difference between portfolio returns and benchmark returns; 2-4% tracking error indicates diversified portfolio with modest tilts, >6% suggests concentrated bets.

Total Return

Portfolio performance including price appreciation, dividends, and interest; total return = (Ending Value - Beginning Value + Income) / Beginning Value.

Volatility (Standard Deviation)

Statistical measure of return dispersion indicating risk; S&P 500 volatility is 15% annually, meaning returns typically vary ±15% from average in two-thirds of years.

Updates

This glossary will be updated as portfolio construction methods evolve and new terms gain adoption in the investment community.

References

Fama, E., & French, K. (2015). A Five-Factor Asset Pricing Model. Journal of Financial Economics.

Markowitz, H. (1952). Portfolio Selection. Journal of Finance.

S&P Dow Jones Indices. (2023). SPIVA US Scorecard: Active Fund Performance vs Benchmarks.

Vanguard. (2022). Sector Rotation Strategies

Evidence from US Markets.