Critical Reasoning (CR) | Re: In the past, when there was no highway speed limit, the highway

In the past, when there was no highway speed limit, the highway accident rate increased yearly, peaking a decade ago. At that time, the speed limit on highways was set at 90 kilometers per hour (kph) (55 miles per hour). Every year since the introduction of the highway speed limit, the highway accident rate has been at least 15 percent lower than that of its peak rate. Thus, setting the highway speed limit at 90 kph (55 mph) has reduced the highway accident rate by at least 15 percent.

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