The Following Stem-And-Leaf Display Reports the Number of Boats Shipped

Short Answer

The following stem-and-leaf display reports the number of boats shipped per week by Ottertail Boats, Inc.
11| 1 5 9
12| 0 1 2 2 6 9
13| 0 1 2 3 4 5 5 7 8 8 9
14| 2 6 8
15| 0 1 2 4 5 7 8 9
16| 1 5 7 9
How many weeks were included in the study?