Simon Willison highlights Anthropic's revenue calculation method, which multiplies the last 28 days of consumption-based sales by 13 and adds it to 12 times the monthly subscription revenue. This approach, while straightforward, may oversimplify revenue projections in the AI sector, where customer usage can fluctuate significantly. The method's effectiveness hinges on stable consumption patterns, which are not guaranteed in a rapidly evolving market. As AI companies strive for financial transparency, such metrics could face scrutiny for their potential to mislead investors.