What do you want to be a dynamic charts, but the chart is more complex, don't know how to implement the

Want to effect: a screening, the Category can be screened (N1, N2 and N3... ), after screening N1 chart, after the screening of N2 also appears corresponding charts, and so on, chart style is roughly as shown in the

Tried once before, but the left side of the merged cell appeared many blank option, after screening the column behind the also don't know how to correspond in screening

Pray god help! Thank you ~ ~ ~!