You've been in your job for a few years now, and your salary hasn't budged. Your thoughts turn to the want ads. Changing jobs for a higher income is a time-honored tradition. Switch jobs too many times, however, and you risk being labeled a job-hopper. With that red flag in mind, we posed a question to several career experts: How often can you safely change employers, if your goal is to earn more money? American workers seem less loyal to their companies today than in the recent past. The median worker had ...