WACC is the average of the costs of these types of financing, each of which is weighted by its proportionate use in a given situation. By taking a weighted average in this way, we can determine how much interest a company owes for each dollar it finances.
Debt and equity are the two components that constitute a company’s capital funding. Lenders and equity holders will expect to receive certain returns on the funds or capital they have provided. Since the cost of capital is the return that equity owners (or shareholders) and debt holders will expect, WACC indicates the return that both kinds of stakeholders (equity owners and lenders) can expect to receive. Put another way, WACC is an investor’s opportunity cost of taking on the risk of investing money in a company.