In 64 fluid ounces, there are 64/8=<<64/8=8>>8 eight-ounce servings.
Using 16-ounce servings, Simeon now drinks 64 ounces in 64/16=<<64/16=4>>4 servings.
Thus, Simeon now drinks his water in 8-4=<<8-4=4>>4 fewer servings per day.
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