What are some of the difficulties involved in defining what a small business is?

Various measures might be used, including the number of people the business employs, the company's sales revenue, the size of the investment required, or the type of ownership structure the business has. The government relies on two different sources for information about small business, and the relationship between these two sources is often not clear. For example, Industry Canada reports that there are 2.2 million business establishments in Canada and about 2.6 million people who are self-employed, but there is no way of knowing how much overlap there is between these two categories. In order to simplify things, a small business is defined as one which is owner-managed and which has less than 100 employees.