Loss runs are foundational tools in insurance, summarizing claim activity and helping underwriters and actuaries assess a policyholder's risk. Yet traditional loss run analysis often falls short. By aggregating all claims, it obscures important trends that vary by claim size, type, and development timeline.
Sub-layer analysis addresses this gap by segmenting losses into distinct layers—revealing nuanced behavior that enables more accurate reserve estimates and better portfolio oversight.
A loss run typically includes:
Sub-layer analysis groups these claims by meaningful dimensions such as size, coverage type, or injury category. This enables insurers to detect development patterns hidden within aggregate totals.
The chain-ladder method extrapolates future payments using historical development factors. Applying this method across sub-layers, e.g., small vs. large claims which improves accuracy.
Steps:
This approach captures unique settlement behavior across different claim severities.
IBNR (Incurred But Not Reported) claims represent future liabilities not yet visible in data. Sub-layer analysis uncovers exposure to delayed reporting, especially in large or complex claims.
Indicators of IBNR gaps:
Segmenting claims reveals which cohorts may be missing, and informs reserve bolstering accordingly.
Different severity layers settle on distinct timelines:
Tracking these independently helps isolate changes in frequency vs. severity—and supports more dynamic reserve responsiveness.
Sub-layer analysis provides visibility into whether severity or frequency is driving loss activity. Key signals include:
Development triangles by severity layer highlight how patterns diverge, improving predictive accuracy for long-tail reserves.
Modern reserving requires speed, scale, and insight. Manual analysis of layered data is resource-intensive. AI and automation change the equation:
AI/ML Capabilities:
Benefits:
Accurate reserves require ongoing recalibration, not just initial estimation.
Best practices:
Behavioral Reserve Risk:
Tools:
Sub-layer analysis elevates reserve management by:
Strategic benefits:
A: Different claim sizes develop at different speeds. Segmenting improves pattern recognition and reserve precision.
A: AI identifies trends across thousands of claims, flagging outliers and improving projection accuracy by layer.
A: Development triangle tools, claim segmentation logic, and platforms capable of tracking reserves by claim cohort.
A: At least quarterly, with higher frequency for volatile or high-exposure segments.
A: Yes. Better-aligned reserves reduce over-reserving and improve ROI on held capital.