To solve this question we have to make deduct these 2 years. 2099 minus 1978 will give the answer.
You are 121 years old.
(1452 months are passed.)
From 1978 to 2099 there are 121 years. If you want to learn your age in 2099 (born in 1978) your age is 121.
Let's see what will be your age if you born +1 or -1 from that date.