Travelers is a major property and casualty insurer selling commercial and personal insurance, including auto, home and business liability coverage, primarily concentrated in the United States. Insurance profitability depends on collecting more in premiums than is eventually paid out in claims and expenses, a relationship tracked through the combined ratio, and Travelers has built a reputation for disciplined underwriting focused on that ratio rather than simply maximizing premium growth. The company's results can be significantly affected by catastrophic weather events like hurricanes and severe storms, since a single major catastrophe can generate claims costs that outweigh a full year of normal underwriting profit in the affected region. Like other insurers, Travelers also earns investment income on the premiums it collects before claims are paid out, giving its results some sensitivity to interest rate movements alongside its core underwriting performance.