In Asia, a 2002 report estimated that 470 million Euro were spent on English Language Teaching materials (source: Association of Educational Publishers). The majority of these expenditures were in Japan (307 million Euro). However, South Korea also plays a large role in these figures. China is seen to be the largest potential market for future growth.
It is difficult to estimate the value of the North American market. In any case, the following gives an excellent indication of the size of this market:
"In 2000, 1,102,261 adults enrolled in ESL programs that received funding through the U.S. Department of Education, Office of Vocational and Adult Education (OVAE). (State-administered Adult Education Program 2000 Enrollment, U.S. Department of Education, Office of Vocational and Adult Education). This number represents 38% of the overall national adult education enrollment of 2,891,895 learners for that year. Adult basic education (ABE) and adult secondary education (ASE, the other components of federally-funded adult education, represented 37% and 25% respectively. University and college students, as well as the many adults served in programs not receiving federal funding, are not included in this number."