With sales of around £2.4bn and publishing operations all around the world, our education business is the largest and most international. It's also the broadest, serving students from pre-school through school and higher education and on into their professional lives; and providing a wide range of services from textbooks to testing and technology-based learning programmes.
The base of our education business is our publishing. Around one in three American schoolchildren learn reading and maths with one of our textbooks, and we publish more than one-third of all US college textbooks. Outside the US, we are a $1.2bn education company, three times the size of our nearest rival. We are the leading publisher for students of English as a second language and have growing businesses in school, college and professional publishing.
We also have leading positions in educational testing and services. Last year we marked 40 million examination papers and administered over one million tests for professional people. We mark school examinations for the US federal government, 20 American states and thousands of UK schools. We provide tests to certify all kinds of professional people including nurses, software engineers and business school applicants, and we manage public information for government customers including the US Departments of Health and Education.
In 2004, our education business moved forward on several fronts. It reported good growth in underlying sales and profits, and laid the ground for faster growth in 2005, which should be a buoyant year in US education. States in America are seeing their budgets recover and planning more textbook purchases, while the federal government is spending more on reading instruction, school testing and professional development of teachers. We've published new programmes in key subjects such as maths, science and music and won some $1bn of new long-term contracts in school and professional testing. And we've made some investments to combine our content, testing and technology into an integrated service for schools and colleges.
So 24,000 American schools are using our technology to help instruct children and manage information about how they are doing; around three million US college students are pursuing their courses online through one of our programmes; and thousands of college professors are teaching from bespoke textbooks that we've published to their own specifications. These services help each student to learn at his own pace, in his own way.
We're confident about the future of our broad-based education business for several reasons. Over the past 10 years our US school and college publishing businesses have grown at an annual rate of around 7%, and our testing businesses have grown faster. Worldwide, estimates put education publishing as a $100bn plus industry, growing at around 5%. The British Council estimates that two billion people, or one-third of the world's population, will be studying English by 2015. In just about every market we're in, governments and individuals have consistently made investing in education - and the learning achievements of students of all ages - a priority.
There has never been a better time to be in the business of education.