Detailed Instructions: This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
Q: Finland has used comprehensive schools since the 1970s, in the sense that everyone is expected to complete the nine grades of peruskoulu, from the age 7 to 16. The division to lower comprehensive school (grades 1–6, ala-aste, alakoulu) and upper comprehensive school (grades 7–9, yläaste, yläkoulu) has been discontinued.
A:
In what decade did Finland begin employing comprehensive schools?