To solve this question we have to make deduct these 2 years. 2120 minus 1978 will give the answer.
You are 142 years old.
(1704 months are passed.)
From 1978 to 2120 there are 142 years. If you want to learn your age in 2120 (born in 1978) your age is 142.
Let's see what will be your age if you born +1 or -1 from that date.