Which graduate degrees today have the highest value (highest average post-grad salary for the lowest amount of debt)

I’d like to get a graduate degree and am exploring my options in all possible academic arenas (engineering, science, medicine, law, business, teaching, accounting, tech) but am extremely hesitant to take on a lot of debt to do so in light of the economy. Specifically I want to know which programs, whether community college certificate programs, second bachelor’s degrees, or master’s or Ph.D. programs, offer the highest potential post-graduate income for the least possible cost. I know this is a “blue sky” type question, but at this point taking out $45,000 for a Masters in Teaching, which pays on average $45,000, doesn’t seem prudent. Thanks all for your thoughts!