Auto Add formated Row on Enter key
 

I'm trying to do a sales report that has a solid continuous border and a
dotted interior. When i get to the last formatted row within the
borders(columns A-G, rows 9-50) and i press enter in row 50 column G i want
it to add another row that pushes the solid continuous border down to row 51
and does the dotted interior. Can anyone provide insight or code?