Data was collected for the number of births per 10,000 people in the United States of America for 20 consecutive years. Below is the data for those 20 consecutive years. Construct a p chart and answer the question below.

157 160 164 167 167 162 158 154 150 146 144 142 143 142 144 141 139 141 140 140
Select the correct lower control limit.