Analysis
Benchmark
Also called comparison set.
Benchmark is a reference value you compare your number against, taken from outside your site or from your own past. It tells you whether a result is high or low.
How it is measured
An internal benchmark is your own earlier period or best result. An external benchmark is a published figure or a peer set. Match the unit, the traffic type, and the definition before you compare, or the gap is meaningless.
Record where the figure came from, the date range, and how the source defined the metric. A published bounce number with an unknown session rule is trivia, not a benchmark.
Worked example
A hosting company sees a 3.4 percent trial-to-paid rate and is told the industry figure is 15 percent. The 15 comes from a report of products with a credit card taken at signup. Their trials need no card.
They switch to an internal benchmark: the best quarter two years ago was 4.1 percent. That gives a gap of 0.7 points, a number they can chase, and it does not depend on someone else's signup rules.
How it differs
A benchmark is a point of comparison. A KPI is a target a team has committed to. A benchmark can inform a KPI but does not bind anyone to reach it.
Common errors
Comparing against a different business model. Using a stale published figure. Treating an average as a goal. Mixing mobile and desktop mixes. Forgetting the benchmark's definition of a metric.
In practice
Choose one internal benchmark first: your own last comparable period. Add an external one only when you can confirm the definition matches. State both beside the result.