The advance-to-decline ratio, indicating market breadth, fell below one for the second month in December, signaling weakening participation despite benchmark indices near record highs. Experts note that recent rallies are driven by a few large-cap stocks, while broader market segments face selling pressure. This divergence suggests cautious investor sentiment, with a preference for fundamentally strong companies and earnings visibility. Analysts advise focusing on quality stocks amid market volatility and selective sector outperformance.