To solve this question we have to make deduct these 2 years. 2115 minus 1978 will give the answer.
You are 137 years old.
(1644 months are passed.)
From 1978 to 2115 there are 137 years. If you want to learn your age in 2115 (born in 1978) your age is 137.
Let's see what will be your age if you born +1 or -1 from that date.