Chapter 7: Rating and Premiums (Part 2 of 4) — Book Rate Theory, Technical Pricing, Trend Adjustments & Burning Cost Rating

In general insurance underwriting, setting a rate based purely on raw historical loss data is insufficient to ensure long-term solvency. Underwriters must build technical book rates that account for operational loadings and future economic or environmental trends. When evaluating large commercial or fleet risks where building rates from first principles is impractical, insurers utilize empirical rating models such as the Burning Cost method.

1. Book Rate Theory & Structure of Technical Pricing

Technical pricing (or Book Rate) develops directly from the pure premium rating method. It relies on high-quality statistical data collated at either the market level or intra-company level, including national fire statistics, crime records, and meteorological data.

The Technical Book Rate Formula

The commercial book price is constructed by adding necessary operational loadings to the base pure risk cost:

Book Rate = Pure Risk Premium + Management Expense Loading + Intermediary Commission + Reinsurance Cost + Profit Margin

(Note: Single-line format without fraction lines).

Exclusion of Investment Income

Although insurers earn investment returns on accumulated reserves, statutory book price calculations do not include investment income in the rating formula. Technical pricing must stand on its own underwriting merits to yield an underwriting profit rather than depending on market investment yields.

2. Key Past, Present, and Future Trend Adjustments

Historical statistical data reflect past risk performance. To project accurate future premium requirements, underwriters must apply structured trend adjustments across several key indicators:

• Inflation Dynamics: Claims inflation frequently outpaces general economic inflation. In property, liability, and health lines, replacement costs, medical fees, and repair charges inflate faster than the baseline exposure measures (such as wage rolls or property values).
• Data Coding & Sub-Class Classification: Capturing granular risk attributes (e.g., specific manufacturing sub-processes or construction materials) ensures that loss trends are identified within homogeneous risk groups.
• Legal and Judicial Changes: Changes in statutory liability laws, expanding judicial interpretations, and higher compensation awards by courts significantly increase long-tail claim payouts.
• Technological Advances: Evolving technology alters both loss frequency and severity. While anti-theft tech can reduce frequency, complex electronic components can drive up individual repair costs.
• Product Attractiveness Shifts: High-value technological items (e.g., new smartphones, laptops) carry high theft risk initially. Over time, price declines and widespread availability turn them into commodities, decreasing their moral and physical hazard profiles.
• Climatic Changes & Global Warming: Shifting environmental patterns increase the frequency and severity of natural catastrophes (NATCAT), directly impacting flood and storm risk pricing.
• External Geo-Political Risk Shifts: Unforeseen external events can abruptly alter risk exposure. For example, the International Maritime Bureau reported global piracy attacks rising from 293 in 2008 to 406 in 2009, with Somali coast attacks doubling from 111 to 217 (and ransom costs exceeding $30–$50 million), forcing marine underwriters to recalibrate global transit rates.

3. The Burning Cost Rating Method

For large commercial risks—such as corporate motor fleets or high-turnover liability risks—calculating rates from first principles can be overly complex. Insurers frequently use the Burning Cost method, which calculates the actual loss cost per exposure unit based on the insured's own historical claims experience.

Core Burning Cost Formula

Base Burning Cost Rate = Average Annual Adjusted Incurred Claims / Average Annual Exposure Unit Base

(Note: Single-line format).

Step-by-Step Burning Cost Process

1. Collate Claims History: Gather claims data for a minimum past period of 5 years (excluding the current unexpired year).
2. Calculate Average Annual Claims: Sum paid claims plus outstanding case reserves across the 5 years and divide by 5.
3. Adjust Claims for Trends: Modify past claims figures for inflation, legal shifts, and structural changes (such as acquisitions or disposals of business units).
4. Collate Exposure History: Gather equivalent exposure base data (e.g., total vehicle count, wage roll, or annual turnover) for the same 5 years.
5. Calculate Average Annual Exposure: Divide total 5-year exposure units by 5.
6. Compute Base Rate: Divide average annual adjusted claims by average annual exposure.
7. Add Commercial Loadings: Convert the base burning cost into a final commercial rate by adding loadings for administrative expenses, intermediary commissions, claims inflation, catastrophe reserves, and profit margins.

Required Documentation for Burning Cost

• Claims experience split clearly between claims paid and claims outstanding (case reserves).
• Historical exposure figures (annual turnover, total wage roll, or fleet vehicle counts).
• Historical details of previous insurers over the 5-year evaluation window.
• Documentation of risk improvement programs instituted by the client that demonstrably lower future loss severity or frequency.

4. Practical Step-by-Step Burning Cost Numerical Example

Scenario Setup: Commercial Motor Fleet (5-Year History)

An underwriter is evaluating a commercial logistics fleet over a 5-year period:

• 5-Year Total Adjusted Losses (Paid Claims + Case Reserves): Rs. 25,00,000.
• 5-Year Cumulative Fleet Exposure: 250 vehicle-years (averaging 50 trucks per year).
• Commercial Expense & Profit Loadings: 30% combined loading required on the base burning rate.

Step-by-Step Calculation

1. Calculate Average Annual Claims: Average Annual Claims = Rs. 2,500,000 / 5 years = Rs. 500,000 per year.
2. Calculate Average Annual Exposure: Average Annual Vehicles = 250 vehicle-years / 5 years = 50 vehicles per year.
3. Compute Base Burning Cost per Vehicle: Base Burning Cost = Rs. 500,000 / 50 vehicles = Rs. 10,000 per vehicle.
4. Calculate Final Commercial Premium per Vehicle (Adding 30% Loadings): Final Commercial Premium = Rs. 10,000 / (1 - 0.30) = Rs. 14,285.71 per vehicle.

5. Comparative Matrix: Book Rating vs. Burning Cost Rating

Key Takeaways

1. Structure of Book Rates: Book rates expand on pure premium by incorporating management overhead, commissions, reinsurance costs, and profit margins.
2. Exclusion of Investment Yield: Investment income is excluded from technical rate formulas; underwriting profit must be independently achievable.
3. Forward Trend Adjustments: Past loss statistics must be adjusted for claims inflation, judicial/legal trends, technological changes, and environmental shifts.
4. Burning Cost Application: Burning cost rating calculates individual loss costs per exposure unit using 5-year historical claims data, making it ideal for fleet and commercial risks.

Important Terms & Definitions

• Technical Price / Book Rate: A comprehensive insurance rate built by adding operational expenses, commissions, reinsurance costs, and profit margins to the statistical pure premium.
• Burning Cost: An empirical rating method where average past loss costs per unit of exposure are calculated over a multi-year period (usually 5 years) and loaded for operational expenses.
• Claims Inflation: The rate at which claim settlement costs increase over time, often exceeding general consumer price inflation due to medical, legal, and repair cost factors.
• Case Reserves: Estimated monetary amounts set aside by claims handlers to cover reported but not yet settled losses.