Top 5 Categories of Employment (Industry/Skill) in 2020?
1. Data Analysis - Statistics, graphical interpretation of information, data mining and such
2. Intermediation, management - so broad as to be almost useless to you, but... the Web, the Net, globalisation, all of these probably make the long run average size of the efficient firm, on average, smaller. If you know a lot about an industry or an industrial niche you can connect people and take a cut or a fee for introducing them. This is basically the extension of the import-export firm model to services.
3. Biotechnology - This area is now in something analogous to the stage the IT industry was in in the late 50s, early 60s with the giant semiconductor companies. No one knows what's going to happen but it's going to be BIG. Aiming to be the Intel, Microsoft or Google of the industry is a bad bet but there will be money here in spades.
4. Professional services - Lawyers, Accountants, Bankers, all businesses need these people eventually, they're all skilled profesionals with hard to commoditise skills, with a possible exception for Bankers, a great deal of whose value is in reputations, connections and trust. The Law is a frankly horrible career but if you can provide a service or product lawyers want, you're golden.
Don't go to Law School unless you can get into a Tier 1 School