In Portugal, 32% of the adult population have at least an upper secondary degree. In the Czech Republic, 92% have one.
I have graphed the figures for the European countries in the map below. An interesting pattern emerges with the Northern and the East European countries having the highest percentages. But I wonder to what extent these numbers represents real failures/successes of the secondary educational systems rather than different ways of setting up (and naming) the secondary education levels.
click to enlarge. The link to the map is here.