"x", "y"
  0.5,   42.5
  0.5,   50.6
  1.0,   68.5
  1.0,   80.7
  1.5,   89.0
  1.5,   99.6
  2.0,  105.3
  2.0,  111.8
  2.5,  112.3
  2.5,  125.7