Output from running do_ntile(), do_percent_rank(), and do_cume_dist() on t4.dp_score 

Using ntile().

 bucket |  n   |   min_s    |   max_s
--------+------+------------+------------
      1 | 5000 |    0.00000 |   33.41577
      2 | 5000 |   33.41745 |   37.61929
      3 | 5000 |   37.61952 |   40.42450
      4 | 5000 |   40.42474 |   42.68859
      5 | 5000 |   42.68912 |   44.63344
      6 | 5000 |   44.63349 |   46.38263
      7 | 5000 |   46.38321 |   47.97366
      8 | 5000 |   47.97368 |   49.52608
      9 | 5000 |   49.52624 |   51.02729
     10 | 5000 |   51.02734 |   52.46619
     11 | 5000 |   52.46621 |   53.92146
     12 | 5000 |   53.92151 |   55.34590
     13 | 5000 |   55.34603 |   56.86802
     14 | 5000 |   56.86867 |   58.48624
     15 | 5000 |   58.48660 |   60.24952
     16 | 5000 |   60.24984 |   62.18791
     17 | 5000 |   62.18821 |   64.47986
     18 | 5000 |   64.47995 |   67.35160
     19 | 5000 |   67.35283 |   71.46368
     20 | 5000 |   71.46578 |  100.00000

 Using percent_rank().

      1 | 5000 |    0.00000 |   33.41577
      2 | 5000 |   33.41745 |   37.61929
      3 | 5000 |   37.61952 |   40.42450
      4 | 5000 |   40.42474 |   42.68859
      5 | 5000 |   42.68912 |   44.63344
      6 | 5000 |   44.63349 |   46.38263
      7 | 5000 |   46.38321 |   47.97366
      8 | 5000 |   47.97368 |   49.52608
      9 | 5000 |   49.52624 |   51.02729
     10 | 5000 |   51.02734 |   52.46619
     11 | 5000 |   52.46621 |   53.92146
     12 | 5000 |   53.92151 |   55.34590
     13 | 5000 |   55.34603 |   56.86802
     14 | 5000 |   56.86867 |   58.48624
     15 | 5000 |   58.48660 |   60.24952
     16 | 5000 |   60.24984 |   62.18791
     17 | 5000 |   62.18821 |   64.47986
     18 | 5000 |   64.47995 |   67.35160
     19 | 5000 |   67.35283 |   71.46368
     20 | 5000 |   71.46578 |  100.00000

 Using cume_dist().

      1 | 5000 |    0.00000 |   33.41577
      2 | 5000 |   33.41745 |   37.61929
      3 | 5000 |   37.61952 |   40.42450
      4 | 5000 |   40.42474 |   42.68859
      5 | 5000 |   42.68912 |   44.63344
      6 | 5000 |   44.63349 |   46.38263
      7 | 5000 |   46.38321 |   47.97366
      8 | 5000 |   47.97368 |   49.52608
      9 | 5000 |   49.52624 |   51.02729
     10 | 5000 |   51.02734 |   52.46619
     11 | 5000 |   52.46621 |   53.92146
     12 | 5000 |   53.92151 |   55.34590
     13 | 5000 |   55.34603 |   56.86802
     14 | 5000 |   56.86867 |   58.48624
     15 | 5000 |   58.48660 |   60.24952
     16 | 5000 |   60.24984 |   62.18791
     17 | 5000 |   62.18821 |   64.47986
     18 | 5000 |   64.47995 |   67.35160
     19 | 5000 |   67.35283 |   71.46368
     20 | 5000 |   71.46578 |  100.00000