This economic idea transfixed Wall Street and Washington. It may be a mirage.

A new economic indicator has captivated Silicon Valley, Wall Street and Washington.

Technology companies' massive spending on artificial intelligence accounted for half or more of U.S. growth last year, some economists calculated, effectively propping up an otherwise anemic economy.

To President Donald Trump and his advisers, the figures showed that AI is helping spark an economic renaissance that must not be impeded by regulation. To some critics, including Rep. Alexandria Ocasio-Cortez (D-New York), the data revealed an economy dangerously addicted to AI.

Either way, it became conventional wisdom that the technology was now a major engine of growth in the world's largest economy.

But a growing number of forecasters now say the economy's dependence on AI was overstated.