How much has the market changed in the past 30 years? Quite a bit, actually. Online trading was still in its infancy then, for instance. Now it's the norm.

That's not all that has changed. Almost none of the biggest publicly traded companies then (based on annual revenue) are the biggest names now. Here's a look at how they have changed, too.

1994's biggest companies

There's more than one way to measure a company's size. Market capitalization is one of them. A more meaningful measure, however, might be revenue produced in any given year. To this end, here's a rundown of 1994's top publicly traded revenue producers, with that year's total top line not adjusted for inflation.

  • General Motors, $155 billion
  • Ford Motor Company, $128.4 billion
  • ExxonMobil, $113.9 billion
  • Walmart, $67.3 billion
  • IBM, $64.1 billion

Note that 1994's giants reflect the fact that automobile ownership wasn't just a matter of convenience at the time, but a lifestyle purchase.

Today's largest companies

And today's biggest players as measured by revenue for the past four reported quarters? No major surprises.

  • Walmart, $657.3 billion
  • Amazon, $604.3 billion
  • Saudi Aramco, $495.1 billion
  • China Petroleum and Chemical (Sinopec Group), $444.8 billion
  • PetroChina, $430.7 billon

Honorable mention is also awarded to Apple, which has done $385.6 billion worth of business over the past 12 months. It's just clear that oil and gas remain a much bigger business than consumer technology currently is.

The only constant is change

Sure, Walmart earned a spot on both lists, and ExxonMobil came pretty close for 2024. The takeaway for investors, however, is that it's difficult for any company to remain dominant indefinitely. Circumstances change; competitors get better. It's a pretty safe bet that most of these names, if not all, will be left off this list 30 years from now. So don't get too committed to a particular stock.