macro to hide rows if cell is blank, unhide if it contains text

I apologize for posting three times in one day. I'm trying to learn the art Excel manipulation.

I'm using a macro to do the following:

Hide rows 45 through 94 if cell R44 contains nothing
Unhide rows 45 through 94 if cell R44 contains any text

That's it. It is simple but I keep missing something, The workbook is protected but cell R44 is not. No formula in the cell.

Thanks for the help. This is what I have but it isn't working.

Sub Worksheet_Change(ByVal Target As Range)

If Range("R44") <> "" Then
Rows("45:94").EntireRow.Hidden = True
Else
Rows("45:94").EntireRow.Hidden = False
End If

End Sub

Also, I need for it to run automatically each time the value of R44 changes,

Thanks for the help!