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: When the railroad was extended through Madison in 1875, larger mills were built. The first Madison Woolen Mill was constructed in 1881 near the bridge between Madison and Anson, with the firm's second mill built nearby in 1887. In 1890, the Manufacturing Investment Company built a sulfite mill, but it failed. It was taken over in 1899 by the Great Northern Paper Company, which rebuilt the plant to produce wood pulp and paper. Like many New England textile manufacturers, the town's woolen mills eventually went out of business, but the pulp and paper mill remains today as the Madison Paper Industries which will close by May 2016 due to low demand for supercalender paper and Canadian competition. In 1901, Lakewood Summer Theatre opened in East Madison on the western side of Lake Wesserunsett. Since 1967 it has been the official summer theatre of Maine, and the oldest continually operating summer theatre in America. Actors who have performed at Lakewood include John Travolta, Carol Channing, and Phyllis Diller Completed in 2007 is the largest structure by volume in Maine, the Backyard Farms greenhouse that covers 24 acres .
How many years after Lakewood Summer Theatre opened in East Madison did it become the official summer theatre of Maine?