Like investment in machinery, investment in human capital involves a financial outlay now in order to generate future income. How does the individual decide how much to invest in education? A useful technique used in investment appraisal is cost-benefit analysis which compares the costs and benefits of a project (see also Chapter 14). All of the costs and all of the benefits of a project need to be identified and quantified in monetary terms. Consider the choice faced by an 18-year-old on leaving school – to go on to higher education or to get a job. The costs of going on to higher education are all incurred now – the cost of the course, the cost of books, living expenses and also the opportunity cost of staying on in education – the salary that would have been earned if the individual had entered employment. The benefits are mostly in the future – a greater likelihood of securing a good job and the increased earnings that can be expected. These costs and benefits cannot be directly compared since the value of money is not the same now as in the future because of the impact of inflation. Future flows of money need to be discounted at an appropriate rate of interest. Once this has been done, the costs and benefits can be compared and the net present value can be calculated. If this is positive, the benefits outweigh the costs and it is worth the individual staying on in education.