Which factor is NOT considered by an insurer when determining fixed annuity payments?

When determining fixed annuity payments, an insurer primarily evaluates factors that influence the guarantee of payment and the stability of income for the annuitant. The correct choice, which focuses on stock market value, is not considered because fixed annuities are designed to provide guaranteed returns that do not fluctuate based on stock market performance. Instead, fixed annuities rely on contractual guarantees from the issuer, ensuring that the annuity holder receives a specific amount regardless of external market conditions.

In contrast, factors like expenses directly affect the net amount available for payments, interest rates influence the earnings of the insurer on the premiums collected (which can affect the terms of the annuity), and the accumulation amount represents the total value of the funds accumulated before the annuitization process occurs. These aspects directly impact how fixed annuity payments are calculated, while stock market dynamics are irrelevant to the fixed structure of these financial products. Therefore, the fixed nature of annuity payments is established independent of how the stock market performs.