Given the task definition and input, reply with output. This task involves creating questions from a given passage that involve some kind of complex reasoning (including numerical reasoning).
The generated questions must require looking at more than one part of the passage to answer. Try to use a variety of reasoning types in your questions (some of the sample reasoning types are illustrated in the 'positive examples' field) and also have a variety of answer types (spans, numbers, dates). A span is a continuous phrase taken directly from the passage or question. In such questions, the answer spans are recommended to be five words. Questions with answer type "number", are expected to start with "How many". For instance, "How long did an event last?" can be phrased as "How many years did an event last?". To increase diversity, try to create more questions for which the answer will be multiple spans. Please create questions that require AT LEAST 2 arithmetic operations as illustrated in the 'positive examples' field. You are encouraged to try DIFFERENT COMBINATIONS of operations and not just limit to the combinations shown in those examples. The more challenging questions you create, the better it is.

Passage: Attitudes toward marriage have changed substantially since World War II. Most obvious was the declining marriage rate, which dropped from 8.5 marriages per 1,000 Finns in 1950 to 5.8, in 1984, a decline great enough to mean a drop also in absolute numbers. In 1950 there were 34,000 marriages, while in 1984 only 28,500 were registered, despite a growth in population of 800,000. An explanation for the decline was that there was an unprecedented number of unmarried couples. Since the late 1960s, the practice of cohabitation had become increasingly common, so much so that by the late 1970s most marriages in urban areas grew out of what Finns called "open unions." In the 1980s, it was estimated that about 8 percent of couples who lived together, approximately 200,000 people, did so without benefit of marriage. Partners of such unions usually married because of the arrival of offspring or the acquisition of property. A result of the frequency of cohabitation was that marriages were postponed, and the average age for marriage, which had been falling, began to rise in the 1970s. By 1982 the average marriage age was 24.8 years for women and 26.8 years for men, several years higher for both sexes than had been true a decade earlier.
By how many years did the marriage age for women and men differ in 1982?