Cancer mortality. An article in the Iberoamerican Journal of Medicine (Vol. 2, 2020) used statistical process tools to monitor the annual cancer mortality rate in the United States. Data on the annual number of cancer deaths per 100,000 affected individuals were graphed from 1960 to 2017 in an x-chart. The individuals’ control chart is shown below. Although none of the mortality rates fall outside the control limits (Rule 1), there is at least one other pattern analysis rule that the data follow. Identify this rule. Is this cause for concern or positive news with regard to cancer mortality in the United States?