Alongside the marquee list every year, from as early as 1956, Fortune staff published sublists of nonindustrial companies, on which Bank of America, American Airlines, Kroger, and others appeared. As the decades went on, these lists became ever more prominent, giving way to a full-fledged Service 500 in 1983.

Finally in 1995, the main list bridged the industrial/service divide. As Thomas A. Stewart wrote in the pages of the 1995 Fortune 500 issue, he and his colleagues had decided that the Fortune 500 should reflect the “change in the structure of corporate America” that was causing the distinction between an industrial company and a service company to fade “as fast as a tan line in September.”

“Phone companies compete with broadcasters, software manufacturers offer personal-finance services, airlines sell mutual funds, automakers write insurance,” Stewart wrote. “Digitization and deregulation” were the primary factors contributing to this shift. Companies that once manufactured all of their products were increasingly outsourcing that work overseas. Telecommunications and financial services companies began bringing in substantial revenue when regulations on those industries eased. Meanwhile, as Stewart wrote: “Most software is indisputably manufactured—you buy it in boxes.”

After the Fortune 500’s change in methodology, half of a company’s sales no longer had to come from manufacturing or mining for the company to qualify for the main list, and newcomers to the top 10 included Wal-Mart Stores (No. 4), AT&T (No. 5), and Sears Roebuck (No. 9).

The 2025 Fortune 500 list, published this past Monday, “has never been more stable” year over year, as Fortune executive editor Matthew Heimer points out. But the list, based on companies’ performance last year, doesn’t yet reflect the effects of President Trump’s tariffs or other actions of the administration. We likely won’t go as far as amending our methodology next year—but as a new world order emerges and AI and other technologies take over, never say never.