Dawn,
Sure. A numeric picture switch. From Word's Help file:
Specifies different number formats for positive and
negative results. For example, if the bookmark Sales95 is
a positive value, the field { Sales95 \# "$#,##0.00;-
$#,##0.00" } displays the value with regular formatting —
for example, "$1,245.65". A negative value is displayed
with bold formatting and a minus sign — for example, "-$
345.56".
See General Switches>Numeric picture for more examples.