The software processes
all of the rows in the entire data set unless you specify a range
of rows with the STARTOBS= and ENDOBS= options. If the ENDOBS= option
is used without the STARTOBS= option, the implied value of STARTOBS=
is 1. When both options are used together, the value of STARTOBS=
must be less than the value of ENDOBS=.
When STARTOBS= is used
in a WHERE expression, the STARTOBS= value represents the first row
on which to apply the WHERE expression.