Assigning a variable and pasting variable to last unused column.

[Ageia]

Hi all.
Rather then waste another 4 hours trying to figure this out, ill just ask.

I need to assign a variable to equal a Constant variable, then I need to find the last unused row on the worksheet, then paste that variable down the column (1-12200 or so rows). I also need to assign Strings for the first two Rows in the target column.

Dim FilterPressureDrop as String
Dim °C as String 
Dim Cons as Double
'Constant of FilterPressureDrop
Cons = -99 
'Write Data to last used column on sheet1 after all calls have been done. 
Sheets("Sheet1").Select
Columns("A:A")

Sorry, dont have much VB experience.