I'm looking at some data for a particular page in my journey YTD, so there is a calculated metric to provide figures for unique visits to that page month by month.
However when i duplicate the table and break it down further by a custom segments to split this figure between age ranges for some reason the total of all the new columns is more than the original.
I know there is some data that falls outside the age ranges i have asked for and even some showing as unspecified, but these would surely add even more to this new total.
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The totals of the table on the right are 21732 compared to the original(base) figure of 21159
Any idea what is happening?