Something like this?
Sheet1
<TABLE style="PADDING-RIGHT: 2pt; PADDING-LEFT: 2pt; FONT-SIZE: 11pt; FONT-FAMILY: Calibri,Arial; BACKGROUND-COLOR: #ffffff" cellSpacing=0 cellPadding=0 border=1><COLGROUP><COL style="FONT-WEIGHT: bold; WIDTH: 30px"><COL style="WIDTH: 64px"><COL style="WIDTH: 64px"><COL style="WIDTH: 64px"><COL style="WIDTH: 64px"><COL style="WIDTH: 64px"></COLGROUP><TBODY><TR style="FONT-WEIGHT: bold; FONT-SIZE: 8pt; BACKGROUND-COLOR: #cacaca; TEXT-ALIGN: center"><TD> </TD><TD>A</TD><TD>B</TD><TD>C</TD><TD>D</TD><TD>E</TD></TR><TR style="HEIGHT: 18px"><TD style="FONT-SIZE: 8pt; BACKGROUND-COLOR: #cacaca; TEXT-ALIGN: center">2</TD><TD>RGA</TD><TD style="TEXT-ALIGN: right">-100</TD><TD> </TD><TD> </TD><TD style="TEXT-ALIGN: right">100</TD></TR><TR style="HEIGHT: 18px"><TD style="FONT-SIZE: 8pt; BACKGROUND-COLOR: #cacaca; TEXT-ALIGN: center">3</TD><TD>GRA</TD><TD style="TEXT-ALIGN: right">50</TD><TD> </TD><TD> </TD><TD style="TEXT-ALIGN: right">50</TD></TR></TBODY></TABLE>
<TABLE style="FONT-SIZE: 10pt; BORDER-LEFT-COLOR: #00ff00; BORDER-BOTTOM-COLOR: #00ff00; COLOR: #000000; BORDER-TOP-STYLE: groove; BORDER-TOP-COLOR: #00ff00; FONT-FAMILY: Arial; BORDER-RIGHT-STYLE: groove; BORDER-LEFT-STYLE: groove; BACKGROUND-COLOR: #fffcf9; BORDER-RIGHT-COLOR: #00ff00; BORDER-BOTTOM-STYLE: groove"><TBODY><TR><TD>Spreadsheet Formulas</TD></TR><TR><TD><TABLE style="FONT-SIZE: 9pt; FONT-FAMILY: Arial" cellSpacing=0 cellPadding=2 border=1><TBODY><TR style="FONT-SIZE: 10pt; BACKGROUND-COLOR: #cacaca"><TD>Cell</TD><TD>Formula</TD></TR><TR><TD>B2</TD><TD>=IF(A2="RGA",-E2,E2)</TD></TR><TR><TD>B3</TD><TD>=IF(A3="RGA",-E3,E3)</TD></TR></TBODY></TABLE></TD></TR></TBODY></TABLE>