Actuarial Science and Math Finance:
I am the director of the graduate program in actuarial science and quantitative risk management. This is a unique degree which is at the intersection of actuarial science and mathematical finance. These areas, historically, have been linked very closely. Though recently the actuarial science profession has moved a little away from mathematical finance, there is a great deal of overlap in terms of tools and techniques. Our industry connections strongly value interdisciplinary programs such as ours, and we expect that demand for such programs will continue to grow. Our graduate program is an extension of our extremely successful undergraduate majors in these areas.
The actuarial science major within the math department is one of the most popular majors at OSU. There is no doubt that this is in part due to the fact that actuarial scientist is often rated as one of the best jobs in the United States. It doesn't hurt that the salary range for actuarial scientists is probably the highest among all undergraduate majors; maybe starting salaries in some of the engineering majors beat us.
Math finance is a closely related major, though geared a little more towards students interested in the finance industry. Students interested in quantitative finance will most likely need to earn a graduate degree as well.
A great source to compare career prospects across majors is DataUSA. According to them, average salaries for actuaries in the US is about $175k, and about $290k for math majors in finance.