Fixed, Variable and Semi-Variabable Costs
Another way of categorising costs in ODL institutions is to consider whether a change in the level of productive activity (for example, by enrolling more students) has an impact on expenditure.
For example, regardless of whether an ODL institution has a hundred registered students or a hundred thousand, it needs to employ a chief executive officer (CEO) or director. Although the duties of the post and the salary on offer would very likely be different in the two situations, the salary of the CEO is considered a fixed cost. However, just because some item of expenditure is categorised as a fixed cost, this doesn't mean it can't change from year to year. The CEO's salary is likey to rise in line with general wage increases, but it remains a fixed cost.
By way of contrast, variable costs increase or decrease in line with learner numbers.
Expenditure for printing study materials is a good example of a variable cost. For each additional student enrolled for a course, extra expenditure is incurred.
Some costs seem stable for a particular level of activity, but suddenly increase with a significant increase in student numbers.
For example, most ODL institutions have policies regarding the maximum number of students who can be accommodated in a class group for face-to-face tutorials. When student numbers exceed the maximum, then a second class group is formed, necessitating the employment of another tutor (or additional hours for the same part-time tutor).
This exercise highlights the fact that, while many costs appear to be fixed at first glance, they are really semi-variable. Take, for example, the salary of the institution’s CEO or Director. When student numbers are low, the CEO will most likely have responsibility for many tasks related to the supervision of staff and the day-to-day running of the institution. However, if student numbers grow dramatically, it is often necessary to buy in specialised services or employ extra managerial or professional staff to take over some of these duties. Thus, even though the institution still has only one CEO, the job that he or she originally carried out has been split among a number of additional employees, with an accompanying increase in costs.