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Anomaly Time Series

Area chart that auto-detects anomalies via z-score and surfaces the top deviation as a plain-language narrative.

State
Size
Mode

Monthly recurring revenue

4,758,780

1 anomaly flagged at 2σ

  • Revenue
  • Anomalies

Revenue dropped to 3,950,000 on Feb 5, 2026, 2.6σ below a 4,500,741.717 baseline — driven by Stripe outage.

Acme · billing data · updated hourly

Demo data is illustrative. Replace with your own typed data prop.

How it computes

Z-score outlier detection: flag points whose standardized deviation exceeds a threshold.

zᵢ = (xᵢ − μ) / σ;  flag when |zᵢ| ≥ threshold (default 2σ)

Assumptions

  • The series is approximately Gaussian.
  • Anomalies are independent rather than clustered.
  • The threshold is symmetric across both tails.

Honest about

  • Threshold is an explicit knob — 1.5σ (loose), 2σ (standard), 3σ (strict) — so the sensitivity is your decision, not a hidden default.
  • If every sample is identical, σ = 0 ⇒ all z = 0 ⇒ no false anomalies.
  • No multiple-testing correction: with enough points some |z| ≥ 2 are expected by chance.