Which of the following is not a factor that affects balance sheet metrics?

The equity risk premium primarily pertains to the expected return that investors require for taking on the risk of investing in the stock market over a risk-free rate. While it plays a significant role in influencing investment decisions and valuations, it is not a direct factor that affects balance sheet metrics such as assets, liabilities, or equity directly.

Balance sheet metrics are influenced by factors such as fair value, which refers to how assets are appraised or reported on the balance sheet at their current market value rather than historical cost. Company size premium and comparative industry risk relates to how the financial ratios and metrics may be adjusted or interpreted based on the size of the company or the specific risks of the industry in which it operates. These factors directly impact how assets and liabilities are valued and presented on the balance sheet, reflecting the company's financial position at a given time.

Therefore, while the equity risk premium is important in a broader financial context, it does not affect the components that directly shape balance sheet metrics.