5 ++---------+-----------+----------+----------+----------+-----------+----------+---------+A
      +          +           +          +          +          +           +          +          +
      |                                                                                         |
      |                                                                                         |
  4.5 ++                                                                                       ++
      |                                                                                         |
      |                                                                                         |
      |                                                                                         |
      |                                                                                         |
    4 ++                                                                  A                    ++
      |                                                                                         |
      |                                                                                         |
      |                                                                                         |
  3.5 ++                                                                                       ++
      |                                                                                         |
      |                                                                                         |
      |                                                                                         |
    3 ++                                           A                                           ++
      |                                                                                         |
      |                                                                                         |
      |                                                                                         |
      |                                                                                         |
  2.5 ++                                                                                       ++
      |                                                                                         |
      |                                                                                         |
      |                                                                                         |
    2 ++                     A                                                                 ++
      |                                                                                         |
      |                                                                                         |
      |                                                                                         |
      |                                                                                         |
  1.5 ++                                                                                       ++
      |                                                                                         |
      |                                                                                         |
      +          +           +          +          +          +           +          +          +
    1 A+---------+-----------+----------+----------+----------+-----------+----------+---------++
      1         1.5          2         2.5         3         3.5          4         4.5         5