Over the past few decades the cost structure of manufacturing companies has sh

Over the past few decades the cost structure of manufacturing companies has shifted. In the early 1900s direct material costs were
substantial while fixed costs represented a small fraction of total manufacturing costs. However the cost structure has reversed and now fixed costs make up
the majority of total manufacturing costs. What caused this to happen? What would explain the drastic change in cost structure? Which industries would be most
affected by this change?

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