Oracle 18c

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CREATE TABLE data
    ("Date" date, Id varchar2(2), "Value" varchar2(2))
;

INSERT ALL 
    INTO data ("Date", Id, "Value")
         VALUES (to_date('2019-02-09', 'YYYY-MM-DD'), 'a1', 'ab')
    INTO data ("Date", Id, "Value")
         VALUES (to_date('2019-01-12', 'YYYY-MM-DD'), 'a2', 'cd')
    INTO data ("Date", Id, "Value")
         VALUES (to_date('2019-12-12', 'YYYY-MM-DD'), 'a1', 'ab')
    INTO data ("Date", Id, "Value")
         VALUES (to_date('2017-07-23', 'YYYY-MM-DD'), 'a1', 'ab')
    INTO data ("Date", Id, "Value")
         VALUES (to_date('2018-12-09', 'YYYY-MM-DD'), 'a1', 'ab')
    INTO data ("Date", Id, "Value")
         VALUES (to_date('2018-12-28', 'YYYY-MM-DD'), 'a1', 'cd')
    INTO data ("Date", Id, "Value")
         VALUES (to_date('2016-11-09', 'YYYY-MM-DD'), 'a2', 'cd')
    INTO data ("Date", Id, "Value")
         VALUES (to_date('2016-05-19', 'YYYY-MM-DD'), 'a2', 'ab')
SELECT * FROM dual
;
8 rows affected

SELECT d.Id,
       COUNT(CASE WHEN EXTRACT(YEAR FROM "Date") = Max_Year THEN 1 END) -
       COUNT(CASE WHEN EXTRACT(YEAR FROM "Date") = Min_Year THEN 1 END) AS "Max-Min"
FROM data d
JOIN (SELECT Id, 
             MAX(EXTRACT(YEAR FROM "Date")) AS Max_Year,
             MIN(EXTRACT(YEAR FROM "Date")) AS Min_Year
      FROM data
      GROUP BY Id) m ON m.Id = d.Id
GROUP BY d.Id


ID
Max-Min


a1
1

a2
-1