Obs   y     x1   x2    x3
1   65.6   28.0  21  174.0
2   71.8   30.8  23  175.3
3   80.7   31.7  28  193.5
4   72.6   28.2  23  186.5
5   78.8   29.4  22  187.2
6   74.8   31.3  21  181.5
7   86.4   31.7  26  184.0
8   78.4   28.8  27  184.5
9   62.0   27.5  23  175.0
10  81.6   28.0  21  184.0
11  76.6   30.3  23  180.0
12  83.6   29.7  22  177.8
13  90.0   31.4  20  192.0
14  74.6   28.0  26  176.0
15  71.0   28.6  23  174.0
16  79.6   30.6  22  184.0
17  93.8   29.4  30  192.7
18  70.0   30.0  22  171.5
19  72.4   29.5  29  173.0
20  85.9   32.6  22  176.0
21  78.8   32.0  22  176.0
22  77.8   32.0  20  180.5
23  66.2   30.9  22  172.7
24  86.4   32.8  24  176.0