To solve this question we have to make deduct these 2 years. 2090 minus 1951 will give the answer.
You are 139 years old.
(1668 months are passed.)
From 1951 to 2090 there are 139 years. If you want to learn your age in 2090 (born in 1951) your age is 139.
Let's see what will be your age if you born +1 or -1 from that date.