In the visualization below you see that in 1970 there were only around 700 million people in the world that had secondary or post-secondary education. By the end of this century the number of people with secondary or post-secondary education will have increased 10-fold and will reach 7 billion people (a similar number as the world population today)!
The projection also shows that the number of people with no education will decrease continuously and that by the end of this century virtually all people in the world will have received some level of education.
Keep in mind, though, that these upward trends in education will not come about automatically. It takes political will and money to increase levels of education, and those of us who know how important education is to the future of human society cannot let down our vigilance. There are plenty of leaders of countries who do not want their people, especially women, to become better educated.