Why is Pfizer falling/rising?

As of 18-Sep, Pfizer Ltd. is experiencing a decline in its stock price, currently at 5,173.30, which reflects a decrease of 28.3 points or 0.54%. The stock has underperformed its sector today by 1.59%, with an intraday high of Rs 5,311.9, indicating some volatility. Over the past week, the stock has seen a slight decrease of 0.13%, and its performance over the last month shows a more significant drop of 10.18%. Despite having a high management efficiency with a return on equity of 18.22% and a low debt-to-equity ratio, the stock's recent performance has been hindered by falling investor participation, as evidenced by a 40.25% drop in delivery volume compared to the 5-day average.
In the broader market context, Pfizer's recent performance contrasts sharply with the Sensex, which has gained 1.80% over the past week and 2.14% over the past month. This disparity highlights the stock's struggles relative to the overall market. Year-to-date, Pfizer has declined by 1.54%, while the Sensex has risen by 6.24%, further emphasizing the stock's underperformance. The high dividend yield of 3.17% may provide some support, but the overall trend suggests that investor sentiment is currently negative, leading to the stock's decline.