To solve this question we have to make deduct these 2 years. 2120 minus 1991 will give the answer.
You are 129 years old.
(1548 months are passed.)
From 1991 to 2120 there are 129 years. If you want to learn your age in 2120 (born in 1991) your age is 129.
Let's see what will be your age if you born +1 or -1 from that date.