Excel - pivot charts, filtering out data points

Hi. I am working on an Excel 'database' where I have 1 datapoint per row with multiple tags eg Rows 1 - 50 contain info for subject 1 where A1 = ID#, B1 = Gender, C1 = Parameter, (eg height, weight etc, D1 = value, (eg height score) etc etc Therefore for the first 50 rows only columns C and D change to indicate the changing parameter (height, weight, armspan etc) and their subsequent score. I am trying to create a pivot chart that graphs this data (easy to do). Less easy to do is include or exclude subjects in the chart based upon whether we have repeated scores on them or not.

We have 8 testing blocks within the dataset which are paired together. I can only include them in the chart if they have data in both 'pairs (pre and post)' eg if they attended testing block 1 but not 2 I can't include the data, but if they attended 3 and 4 I want to include that data (I hope this is making sense, ti isn't easy to explain!) In essence I think I am looking for a nested IFISBLANK command where I can perform some sort of check to see whether they have data in each testing pair and from that produce a filter which I can add into my pivot chart! I think this is a little more complicated than usual as our dataset runs vertically rather than horizontally and we now have 20,000 lines of data!