Consider the relationship between the number of hours a junior high student is left unsupervised at home each day and their corresponding overall grade average. The following sample was collected:

Hours Unsupervised	Overall Grade Average
0	96
0	91
0.5	88
1.0	92
1.0	94
1.5	91
2.0	87
3.0	85
3.0	81
4.0	80
4.5	77
5.5	72

Find the linear correlation coefficient to three decimal places.

If the correlation coefficient cannot be determined, type 123456.