There are ten bird baths in a park. On the first day of​ spring, the bird baths are filled. Several weeks​ later, the overall change in the water level is found. The results are shown in the table. What is the range of the​ data?
2.5
0.7
-2.2
2.1
2.3
-1.6
1.1
-2.4
2.7
1.2