Most Recent Filled Cell = Reference

The program is more complex but I am essentially looking to complete the following:

On sheet1 I have a range of cells (lets say its all of column D), when a value is entered into that range (say D1) that value fills to cell A1 on sheet2... Easy enough../However, when a cell value is entered into sheet1 D2 with the value of D1 still there, I need A1 of sheet2 to autofill with the value of D2 (also will keeping the D1 sheet1 value intact)....

Basically looking for sheet2 to update with the most recent entry until the A1 is either manually deleted or another value is entered in the sheet1 range.

Any suggestions would be greatly appreciated.

Close but this doesn't allow for entries out of order. ie: enter D1, value fills in A1...Enter D3, value fills A1...But then enter D2, value does not fill in A1.

Thanks very much for the feedback though!