Does your column of data have blank cells throughout the column? Are you asking for the chart data not to use the blanks within the range?
If so, I don't think your going to get what you want. A chart series has to be contiguous (continuous, uninterrupted set of data) range. If you need your non-blank cells aggregated together, we would have to go a different way.
Dynamic named ranges count the number of non-blank cells and return a row. You can have it return the last non-blank row. In your case, Countif is only counting the non-blank cells. It won't include all the data if blanks are included.
=offset($AU$6,0,0,match(1e+300,$AU$6:$AU$65),1)
This would return the last row with a number in it. It would still return the full range including any blanks.