+The GROUP subcommand is relevant only if more than one variable is to be
+recoded. It causes a single mapping between source and target values to
+be used, instead of one map per variable.
+
+If /BLANK=MISSING is given, then string variables which contain only
+whitespace are recoded as SYSMIS. If /BLANK=VALID is given then they
+will be allocated a value like any other. /BLANK is not relevant
+to numeric values. /BLANK=VALID is the default.
+