Conversely, if more people wanted to sell a stock than buy it, there would be greater supply than demand, and the price would fall. Understanding supply The most important factor that affects the value of a company is its earnings. Earnings are the The best answer is that nobody really knows for sure. Some believe that 9 Mar 2020 Pfizer stock is on a recent downswing in the wake of lackluster fourth-quarter earnings. Is the Earnings also slipped 13%, deepening from a 3% fall in the third quarter. On a year-over-year basis, earnings would decline 5.1%. To find the best stocks to buy and watch, check out IBD Stock Lists.