Excel charts
 

Can anyone tell me if it's possible to lock or link text boxes or shapes to
the x axis values in a chart. Basicly the x axis is the date in my case with
a data series over time in the chart. I have drawn in vertical lines to
represent date markers wtih grouped text boxes. But when we add more data,
those drawn in lines/text boxes do not re-position automatically to stay
matched with the date I want. Help!