Thank you Wolfgang , a pretty nice informative article of where we are (standstill) but I am not sure we can rely on this to predict that we will only have 6 % of the 70 million having a university degree.
First those who think that 6 % is too small , you might want to check what the other developed nations have attained not as a total of adult population /working population but as a % of the entire population.
Now why I think the projections might not be very reliable , is because they fail to predict the rising changing education delivery technologies. It is akin of the predictions made by a number of institutions that by 2007 the mobile phone subscriber base in Kenya would be about 1 million. We know how this number turned out to be incorrect. Education delivery is under rapid transformation from the emergence of models such as the Khan academy and others and with rapid drop in prices of laptops/tablets etc , I wonder whether such a large number of teachers will be required or the number of classrooms. The same disruptions that we saw in communication technology that deliver rapid affordability and mass usage are what we are about to see with Education, so I think primary school and secondary education (if at all we will use the same categorizations to measure literacy/skills leve attainment by 2050) completions, will be achieved much faster than your predictions Wolf - unless Kenya goes into war and fails to take advantage of these technological developments.
Sorry but economists have been terribly wrong in predicting the magnitudes of technology adoption impacts.