Consolidated Underwriting Income (Loss)/Underwriting-Related General and Administrative Expenses
Corporate expenses include holding company costs necessary to support our worldwide (re)insurance operations and costs associated with operating as a publicly-traded company. As these costs are not incremental and/or directly attributable to our individual underwriting operations, we exclude them from underwriting-related general and administrative expenses and, therefore, consolidated underwriting income (loss). Interest expense and financing costs primarily relate to interest payable on our senior notes and are excluded from consolidated underwriting income (loss) for the same reason.
We evaluate our underwriting results separately from the performance of our investment portfolio. As such, we believe it appropriate to exclude net investment income and net realized investment gains (losses) from our underwriting profitability measure.
As noted above, foreign exchange losses (gains) in our Consolidated Statement of Operations primarily relate to our net insurance-related liabilities. However, we manage our investment portfolio in such a way that unrealized and realized foreign exchange rate gains (losses) on our investment portfolio generally offset a large portion of the foreign exchange losses (gains) arising from our underwriting portfolio. As a result, we believe that foreign exchange losses (gains) are not a meaningful contributor to our underwriting performance and, therefore, exclude them from consolidated underwriting income (loss).We believe that presentation of underwriting-related general and administrative expenses and consolidated underwriting income (loss) provides investors with an enhanced understanding of our results of operations, by highlighting the underlying pre-tax profitability of our underwriting activities.