Update stats page with dropped profile hours info (#13278)

Co-authored-by: Alex Krawiec <[email protected]>

Author: 2 people

docs/product/stats/index.mdx

@@ -159,3 +159,9 @@ The "Metric Alerts Triggered" chart and table show alert rules that have been tr
 #### Number of Releases
 
 The "Number of Releases" chart and table show the releases that were created for each of your team's projects.
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+## Continuous Profiling Stats
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+#### Dropped Profile Hours
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+[Relay](/product/relay/) calculates profile durations for accepted outcomes rather than for every profile chunk received. Both profile hours and UI profile hours stats are derived from these accepted profile chunks or UI profile chunks, respectively, with no duration data stored for dropped outcomes (which are simply counted). Each profile chunk has a maximum duration of 66 seconds. Based on internal testing data the 10th and 25th percentiles of accepted profile chunk durations are approximately 9.9 seconds. This metric was used to select 9.0 seconds as the estimation multiplier for each dropped profile chunk.