A SysOps administrator configures a CloudWatch alarm on the CPUUtilization metric of a production EC2 instance with a threshold of 80%. The metric is emitted every minute, but the workload is naturally spiky — CPU frequently jumps above 80% for a single minute and then drops back down. These brief spikes are triggering frequent alarm state changes and paging the on-call team unnecessarily. The team wants the alarm to trigger ONLY when the instance is genuinely under sustained load, while still reacting reasonably quickly. Which configuration change should the administrator make?