11.1.89.2   %PLUS

Increment tag by specified amount, percentage , tag value or script variable
 

<SETVAL>counter=%PLUS 1 # increments tag named counter by 1.

<SETVAL>tag2=%PLUS 1%	# increments tag2 by 1 percent of span.

<SETVAL>tag2=%PLUS @tag1 #  increments tag2  by  value of tag1