Now today we are gonna touch on a little sensitive topic here.
It is widely promoted to "invest" in yourself and I'm not against that, but here to provide another angle of viewing in it.
What if you looked at education as an investment? (No, do not drop your studies and work. I feel that everyone should get basic education and hopefully a diploma or degree at least)
Say the yield from education is not measured by the pay you get, but rather the amount you have left that is saved (be it in investments, bank savings or whole life insurance/endowments).
Just like the balance/income sheet of a company.
When looking to further study, what is the extra savings, generated from extra pay would you get? That translates to the return on investment or yield.
Something like:
Salary (income) minus expenditure/tax/loan repayments = yield on education
(if you're getting one ......