The following ratios are important for monitoring performance or calculating premiums: 1. Burning ratio. Insurance claims as a percentage of total premiums for current policies. 2. Claims (or loss) ratio. Incurred losses in relation to earned premiums. 3. Expense ratio. Insurers’ total expenses in relation to written premiums. 4. Combined or composite ratio. Sum of (2) and (3), a figure below 100 per cent indicating that an underwriting profit has been achieved.