According to Charlie Bilello, Warren Buffett said in 1999 that it is wildly optimistic to assume corporate profits can hold much above 6% of US GDP for a sustained period. Source: Charlie Bilello on X/Twitter (Dec 7, 2025), https://twitter.com/charliebilello/status/1997706094005883204; Warren Buffett, 1999, as cited by Bilello. This highlights a tradable macro gauge: track the BEA-reported corporate profits-to-GDP ratio versus the 6% long-run anchor to assess earnings sustainability and potential equity valuation risk. Source: U.S. Bureau of Economic Analysis (corporate profits and nominal GDP series), https://www.bea.gov; Warren Buffett, 1999, as cited by Bilello. Because crypto and US equities have shown periods of positive correlation, shifts in this profit-share metric that impact risk sentiment can spill over to BTC and ETH volatility. Source: IMF blog “Crypto Prices Move More in Sync With Stocks, Posing New Risks” (2022); Coin Metrics correlation datasets, https://coinmetrics.io.