Hospitalization rates decreased by 21% per hour of travel by foot and 28% per half hour of travel by vehicle.

每徒步旅行一小时，住院率下降21%，每乘坐交通工具半小时，住院率下降28%。

youdao

Sometimes they give you the speed in miles per hour, kilometers per year, pounds per square foot.

有时候速度的单位是英里/小时,千米/年,英磅/平方米

耶鲁公开课 - 基础物理课程节选

After the vessel was abandoned, it was hit by 40-miles-per-hour winds and 18-foot waves, which caused it to fill with water and sink.

WSJ: Heavy Seas Claim Replica of HMS Bounty

By Sunday, Logan International Airport in Boston, where machines with 27-foot blades and blowers with wind speeds of 450 miles per hour mowed the runways, had resumed operations, as had the three major airports in the New York City area.

WSJ: Northeast Digging Out After Snowstorm