percent decrease from max

percent decrease from max calculates the percent decrease from the maximum value to the current value. For example, given the following case fragment:

           01 Jun 03    20 Jun 03    30 Jun 03    15 Oct 03    02 Nov 03
HDL           2.0          2.1          2.2          2.2          2.3
LDL                        6.2          4.7                       3.1
Trig          3.6                                    3.6
LipidDrug     N                         Y            Y

percent decrease from max HDL is 0

percent decrease from max LDL is 50