Hello gregoir,
repetitive tasks like this can take a week to do manually, or you can use a macro. In this particular instance, create the first two data series manually, then run the following macro to add the other data series automatically. It will create as many data series as are listed in row 5 and below.
You can change the parameters of the macro to suit your workbook.
The code needs to go into a standard module. (If that last sentence means nothing to you, please pipe up and someone will help you to install it in the right place).
cheers,
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