I am looking for a way to have a text box at the top of my dashboard that will update automagically after appending the data table with the new monthly data; to show the latest date of data entered.
You'll need a helper cell to find the latest date then draw your textbox and have it reference the helper cell. The formula to find the latest date would simply be =MAX(A2:A5)(In my example sheet). Reference the example attached.
To have the text box reference the cell simply select the text box and then in the formula bar type the cell reference. Hope this helps.
Thank you. I understand the helper cell. Have used that for other dynamic updates. However in your example if I add a date to the array it does not update to the latest date entered. Is there a way to have the helper cell update the new range when additional data is added?
Thank you for your help.
Kim
Absolutely, for that you will need a dynamic named range. They are amazing and once you know them you will use them often! Then update the formula in your helper cell to reflect the named range instead of the fixed cells. 
Thank you that worked beautifully! Now I am going to figure out how do that with the sum of a column. I love learning new things. Thank you very much for the help. My Dashboard is coming along nicely.
Kim
Glad to help! 
