India’s stock market has seen a remarkable shift in scale over the last decade, in the number of retail participants and how valuations are tracked and discussed. Investors, big and small, often look for signals to make sense of where the market is headed. Among the various metrics used to assess overall market health, the market cap-to-GDP ratio remains a familiar reference point. Known more popularly as the Buffett indicator, it stands alongside other tools like price-to-earnings ratios a...