Benchmark

What Is a Benchmark?

A benchmark is a reference point used to judge how well an investment or portfolio has performed. Investors and fund managers compare returns against a benchmark to see whether a strategy did better or worse than a simple, clearly defined alternative. Many benchmarks are a market index, such as the S&P 500 for large U.S. stocks or the Bloomberg U.S. Aggregate Bond Index for investment-grade bonds. Others are peer group averages or blends of several indexes.

How Benchmarks Work

A fund's benchmark is usually chosen to match its asset class, style, and geographic focus. A large U.S. growth stock fund might use a growth index for large American companies, while an international bond fund might use a global bond index. The benchmark is typically named in the fund's prospectus or shareholder reports, and the fund's results are often shown alongside it.

Performance is usually compared by looking at the difference between the two returns over the same period:

Excess return = Fund total return - Benchmark total return

A positive result means the investment beat its benchmark, and a negative result means it lagged. Because the outcome depends on the period chosen, a single year can tell a different story than a longer stretch.

Why It Matters to Investors

Benchmarks provide context. A fund that gained 8% in a year may look strong, but if its benchmark gained 12%, it underperformed. Benchmarks also help investors judge whether a manager's active management is adding value or whether similar results could have come from a low-cost index fund that simply tracks the benchmark.

Benchmarks have limits. A benchmark may not reflect a fund's actual holdings, and changes in an index's composition can make comparisons less fair over time. The gap between a fund's returns and its benchmark's returns is called tracking error when measured as volatility, and some investors also look at alpha, which estimates return beyond what the fund's market risk would predict. Benchmarks describe what an investment is measured against. They do not predict future results.