Determining the Space Values for Data Classes

To determine the space values for data classes, look at the tape data set size range table produced by the GFTASRT3 phase of the volume mount analyzer. In the sample table shown in Figure 1, 89.8% of the data sets are less than, or equal to, 50 MB.
Figure 1. Example of a Tape Data Set Size Range Table
+--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----+
|        |  # OF |% TOT| CUM # |% TOT|# OF STAT|% TOT| CUM STAT|% TOT|# OF STAT|% TOT| CUM STAT|% TOT|
|DSN SIZE|  DSNS | DSNS|  DSNS | DSNS|  MOUNTS | MNTS|  MOUNTS | MNTS| VOLUMES | VOLS| VOLUMES | VOLS|
+--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----+
| =   0MB|    136|  1.1|    136|  1.1|    113.4|  1.7|    113.4|  1.7|     19.6|  1.5|     19.6|  1.5|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<=   1MB|   7812| 63.1|   7948| 64.2|   3515.5| 53.2|   3628.9| 54.9|    785.9| 59.8|    805.6| 61.3|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<=   5MB|   1149|  9.3|   9097| 73.4|    503.1|  7.6|   4132.0| 62.5|     84.3|  6.4|    889.9| 67.7|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<=  10MB|    402|  3.2|   9499| 76.7|    249.6|  3.8|   4381.7| 66.3|     53.2|  4.0|    943.1| 71.8|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<=  25MB|   1211|  9.8|  10710| 86.5|   1153.7| 17.5|   5535.4| 83.7|    196.0| 14.9|   1139.1| 86.7|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<=  40MB|    323|  2.6|  11033| 89.1|    318.0|  4.8|   5853.4| 88.5|     60.9|  4.6|   1200.0| 91.3|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<=  50MB|     84|  0.7|  11117| 89.8|     50.1|  0.8|   5903.5| 89.3|      9.7|  0.7|   1209.7| 92.1|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<=  75MB|    411|  3.3|  11528| 93.1|    117.3|  1.8|   6020.8| 91.1|     31.4|  2.4|   1241.1| 94.5|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<= 100MB|    332|  2.7|  11860| 95.8|    305.9|  4.6|   6326.7| 95.7|     26.9|  2.0|   1268.0| 96.5|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<= 125MB|    172|  1.4|  12032| 97.1|    112.1|  1.7|   6438.8| 97.4|     15.7|  1.2|   1283.7| 97.7|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<= 150MB|     47|  0.4|  12079| 97.5|     26.3|  0.4|   6465.1| 97.8|      2.5|  0.2|   1286.2| 97.9|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<= 175MB|     76|  0.6|  12155| 98.1|     22.4|  0.3|   6487.5| 98.1|      6.8|  0.5|   1292.9| 98.4|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<= 200MB|     74|  0.6|  12229| 98.7|      3.8|  0.1|   6491.3| 98.2|      1.3|  0.1|   1294.3| 98.5|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<= 300MB|     95|  0.8|  12324| 99.5|      4.3|  0.1|   6495.6| 98.2|      1.0|  0.1|   1295.3| 98.6|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<= 400MB|     31|  0.3|  12355| 99.7|     58.0|  0.9|   6553.6| 99.1|      9.2|  0.7|   1304.5| 99.3|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<= 500MB|      0|  0.0|  12355| 99.7|      0.0|  0.0|   6553.6| 99.1|      0.0|  0.0|   1304.5| 99.3|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|
|<= 600MB|     31|  0.3|  12386|100.0|     58.0|  0.9|   6611.6|100.0|      9.5|  0.7|   1314.0|100.0|
|--------+-------+-----+-------+-----+---------+-----+---------+-----+---------+-----+---------+-----|