Reading the story behind a price.
Median, average, and why a changing collection can change the chart.
Median versus average
A median is the middle observation in a sorted set. An average is the sum divided by the count. The median is often less sensitive to one unusually expensive listing, but neither statistic corrects a poorly matched sample.
The inventory changes
If lower-priced watches disappear and expensive ones remain, the average can rise even when no seller increases a price. A chart of available asking prices is therefore different from a repeat-sales index following the same items over time.
Look for the evidence below the line
Check the sample size, number of retailers, matching criteria and observation date. Missing days should remain visible. We do not manufacture historical points before collection begins or fill sparse periods with invented prices.
Published September 6, 2026. Educational guidance; not an estimate of future investment performance.