Contrary to earlier predictions, demand for wine has not increased in recent years. Yet, even though prices and production amounts have also been stable during the last three years, wine producers last year increased their profits by more than 10 percent over the previous year's level.
Any of the following statements, if true about last year, helps to explain the rise in profits EXCEPT:
【选项】
Wine producers have saved money on wages by switching from paying laborers an hourly wage to paying them by the amount harvested.
选项是否正确？