Signal Decay Horizon

Signal Decay Horizon is the window of time over which a rank-tracking data point still supports a client claim. A daily position from AccuRanker or Nozzle is a snapshot, not a trend; the moment an agency presents it as proof of progress, the clock starts on how long that proof survives an algorithm update or a competitor move. Agencies that set a fixed horizon (for example, 14 days of consistent movement before a ranking is reported as a result) avoid retracting wins mid-retainer. The same logic applies to AI citation tracking: Nightwatch and LLMrefs surface brand mentions in ChatGPT and Perplexity, but a single citation is noise until it repeats across a defined window. The framework forces delivery teams to separate volatile daily movement from reportable signal, which protects retainer credibility when a client checks rankings the morning after a Google update.