Switching majors is a lot easier than switching careers. That is a pretty big jump, direction wise, between Econ/Adv. They're two different disciplines. Your question about, "getting a good job" has more to do with (you) than the career path. Sure the law of supply and demand do apply to both professions, pun intended, However, as a future professional, your passion or interest in the field has to be factored in. My suggestion would be rather than jumping ship right away take the time to understand who you are as a person. What are the things that really interest you the most and let that guide your thought processes? In short, I've personal know someone who pursued financing and investing because he thought that was where the money was and his happiness. (As if money ever makes people happy)
After six months he was ready to hang himself, cause he hated everything about that profession. So much for the money and went back to school. Let me say something to you that you may not have even thought about. Are you ready? Are you sitting down? Whatever it is that you choose to do for a living you'll do it for a very long time. A lot of hour's, occasional nights and weekends, when you're sick or exhausted.
That is is the harsh reality of employment. So behooves you pick something that you are at least interested in. Invest in yourself first because dividends are amazing and you get the highest return. Not just school but life. You can't make a good decision in a vacuum.