"Inflation-adjusted world GDP increased roughly fivefold between 1970 and the mid-2020s."
The World Bank's real GDP series, reproduced by Our World in Data and updated in July 2026, shows that global economic output increased severalfold between 1970 and 2025. This provides empirical context for the contrast between sustained historical economic expansion and the downturn depicted in Forrester's original model run.
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