Rules

Anomaly Formula: Amount-By-Average

What it does:
This rule compares your most recent usage to the average value of all previous usages. If the difference between the most recent value and the average exceeds your defined threshold—and matches the direction you’re monitoring (increase, decrease, or any)—it’s considered an anomaly.

When to use it:
Use this formula when you want to track deviations from your typical usage over time. It helps you catch significant shifts from your average behavior, such as unexpected spikes or drops.

Examples

✅ Example 1: Significant Decrease Triggers Alert

• Anomaly Formula: AmountByAverage
• Change Type: Decreased
• Threshold: 35
• History: 80, 82, 83, 81, 80
• Explanation:
  • Average (Mean) = 81.2
  • Latest value = 80
  • Difference = 80 – 81.2 = -1.2
  • Since the change is not large enough to trigger the alert, no alert is triggered.

❌ Example 2: Increase But Set to Decreased (No Alert)

• Anomaly Formula: AmountByAverage
• Change Type: Decreased
• Threshold: 35
• History: 60, 65, 70, 75
• Explanation:
  • Average (Mean) = 67.5
  • Latest value = 75
  • Difference = 75 – 67.5 = +7.5
  • Since the change is positive and the alert is set to trigger for decreases, no alert is triggered.

✅ Example 3: Sharp Drop Below Average Triggers Alert

• Anomaly Formula: AmountByAverage
• Change Type: Decreased
• Threshold: 35
• History: 120, 110, 115, 130
• Explanation:
  • Average (Mean) = 118.75
  • Latest value = 80
  • Difference = 80 – 118.75 = -38.75
  • Since -38.75 ≤ -35, an alert is triggered.