In general insurance, actuarial analysis provides the quantitative foundation for pricing, reserving, capital allocation, and risk management. While the main body of an actuarial report presents the core findings, the appendices play a critical supporting role. They supply the data, assumptions, computational details, and supplementary results that allow reviewerssenior actuaries, auditors, regulators, and senior managementto validate the analysis and to reproduce it if required. This page outlines the essential components that should be included in the appendices of a generalinsurance actuarial study. The guidance is applicable to a wide range of products (property, casualty, motor, liability, etc.) and to both traditional and emerging actuarial techniques. Fundamentals of General Insurance Actuarial Analysis Appendices
Introduction
Appendices serve three primary purposes:
The following list represents the most frequently encountered appendices. Not all studies will need every item, but the omission of a relevant appendix should be justified in the main body.
List all data files, tables, and extracts used in the analysis. Include:
Provide a summary of validation checks performed:
| Check | Method | Result |
|---|---|---|
| Missing values | Frequency count per column | 0.2% of exposure records |
| Outofrange values | Boundary rules (e.g., negative claim amounts) | None identified |
| Duplicate policies | Policy number uniqueness test | 5 duplicates removed |
Outline each transformation step (e.g., aggregation, censoring, inflation adjustment) with the rationale and the exact formula used.
Describe the statistical or deterministic model employed (e.g., GLM, Bayesian hierarchical model, frequencyseverity approach, stochastic reserving model). Include a diagram if helpful.
Identify software, packages, and versions (e.g., R4.3.1 with actuar and mgcv, Python3.11 with pandas, scikitlearn). Provide a brief description of the computing environment (OS, hardware).
Detail the estimation technique (maximum likelihood, Bayesian MCMC, bootstrap). Mention convergence criteria and any diagnostics performed (e.g., residual plots, deviance, trace plots).
Present the calibrated parameters in a table. Include standard errors and confidence intervals where applicable.
| Parameter | Estimate | Std. Error | 95% CI |
|---|---|---|---|
| Intercept (frequency) | -3.21 | 0.12 | [-3.44, -2.98] |
| LogPremium effect | 0.87 | 0.04 | [0.79, 0.95] |
| Severity shape () | 1.45 | 0.06 | [1.33, 1.57] |
Explain why each assumption is reasonable for the portfolio under review. Cite empirical evidence or industry studies where possible.
Provide a breakdown of expected losses by line of business, region, and policy year.
| Year | Line | Expected Loss | Earned Premium | Loss Ratio |
|---|---|---|---|---|
| 2023 | Motor | $12.5M | $18.0M | 69.4% |
| 2023 | Property | $8.1M | $10.5M | 77.1% |
| 2023 | Liability | $4.3M | $6.2M | 69.4% |
Insert illustrative histograms or density plots for frequency and severity. (In a live site, these would be generated from the analysis code.)
Show the cumulative development factors and the resulting IBNR reserves for the last three accident years.
| Accident Year | Ultimate Loss | Reported to Date | IBNR |
|---|---|---|---|
| 2020 | $22.4M | $19.1M | $3.3M |
| 2021 | $24.0M | $20.5M | $3.5M |
| 2022 | $25.7M | $22.0M | $3.7M |
