They raise the cost of economic activity and allow less of it to take place.

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Based on volumes of activity and current cost structures of many banks, operating costs may need to fall by 20%-45% and the balance sheet by 50%-75%, through closing or selling branches, products, business lines, and even entire regions.

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The true cost of the government assistance for a particular activity (such as subsidizing those paying college tuition) is not obvious.

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To generate the rankings, we made a list of 40 large U.S. metropolitan centers, then ranked each of them in seven areas: nightlife, culture, job growth, number of other singles, cost of living alone, coolness and, for the first time, online dating activity.

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It should be noted, however, that increasing the cost of Business and General Aviation (such as charging higher user fees) would reduce activity levels in this form of air transportation.

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Called TDABC (time-driven activity-based costing), it attempted to relate the measurement of cost to time.

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The cost of reviving the 2% tax on wages for the middle class is expected to reduce economic activity by at least 0.5%.

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The Open Compute Project was the result of an activity at Facebook to build the most efficient computing infrastructures at the lowest possible cost.

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Proponents note that the overall cost of the project would be recouped within a few decades, as the volume of tunnel freight transport activity increased, reaching an estimated 3 percent of the world's total physical cargo or 100 million tons annually.

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