The LOOKUP2 statement can be used to retrieve entries from a table of
Values. If Index is zero, Var is set to the first Value. If Index is one,
Var is set to the second Value. And so on. If Index is greater than or
equal to the number of entries in the list, and Var remains unchanged.
The variable decsec should contain either 0 or 1 since your table is just 2 entries long.