9/30/1981

28.1

6/18/2007

28.01

5/15/1989

25.33

5/8/2015

24.47

5/1/1990

22.8

5/8/1993

22.72

2/19/1997

22.69

6/17/2015

22.29

5/20/2015

22.15

6/30/2007

22.02

5/27/1987

19.77

4/2/1986

19.59

12/19/1991

18.7

10/18/1993

17.02