According to the textbook context, the section titled 'Rising Importance of the Tertiary Sector in Production' directly addresses this question. The context states that 'In the past 100 years, there has been a further shift from secondary to tertiary sector in developed countries' and that 'The service sector has become the most important in terms of total production.' The graphs comparing 1977-78 and 2017-18 show this growth over the forty-year period.