Given the task definition, example input & output, solve the new input case.
This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
Example: Passage: The French and Indian War (17541763) was the North American theater of the worldwide Seven Years' War. The war was fought between the colonies of British America and New France, with both sides supported by military units from their parent countries of Great Britain and France, as well as Native American allies. At the start of the war, the French North American colonies had a population of roughly 60,000 European settlers, compared with 2 million in the British North American colonies. The outnumbered French particularly depended on the Indians. Long in conflict, the metropole nations declared war on each other in 1756, escalating the war from a regional affair into an intercontinental conflict. Question: When was the French and Indian War?
Output: 1754-1763
It is a common convention to write (start year-end year) beside a historical event to understand when the event happened. We can observe a similar notation from the passage to conclude that the French and Indian War happened during 17541763. Therefore, the answer is 17541763.

New input case for you: Passage: The total adult literacy rate is 99 percent. Portuguese primary school enrollments are close to 100 percent. According to the OECD's Programme for International Student Assessment (PISA) 2009, the average Portuguese 15-year-old student, when rated in terms of reading literacy, mathematics and science knowledge, is placed at the same level as those students from the United States, Sweden, Germany, Ireland, France, Denmark, United Kingdom, Hungary and Taipei, with 489 points (493 is the average). Over 35% of college-age citizens (20 years old) attend one of the country's higher education institutions (compared with 50% in the United States and 35% in the OECD countries). In addition to being a destination for international students, Portugal is also among the top places of origin for international students. All higher education students, both domestic and international, totaled 380,937 in 2005. Question: What percentage of college-age citizens attend a higher education institution in the United States?
Output:
50%