But how long before these constructions that make prescriptivists cringe are considered proper usage?

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Proper usage: When two companies merge, the pro forma data give shareholders a point of comparison from one year to the next.

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Following long-standing precedents in food regulation, the FDA requires special labeling only when a new food raises questions of safety, nutrition, or proper usage.

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However, they must adhere to established standards for proper usage.

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