SET SERVEROUTPUT ON
VARIABLE basic_percent NUMBER
VARIABLE pf_percent NUMBER
DECLARE
    today DATE := SYSDATE;
    tomorrow today%TYPE;
BEGIN
    DBMS_OUTPUT.PUT_LINE('Hello World');
    DBMS_OUTPUT.PUT_LINE('TODAY IS : ' || today);
    tomorrow := today + 1;
    DBMS_OUTPUT.PUT_LINE('TOMORROW IS : ' || tomorrow);
    :basic_percent := 45;
    :pf_percent := 12;
END;
/
PRINT basic_percent
PRINT pf_percent