Fills down from the top cell or cells in the specified range to the bottom of the range. The contents and formatting of the cell or cells in the top row of a range are copied into the rest of the rows in the range.
expression.FillDown
expression Required. An expression that returns a Range object.
Example
This example fills the range A1:A10 on Sheet1, based on the contents of cell A1.
Worksheets("Sheet1").Range("A1:A10").FillDown