To solve this question we have to make deduct these 2 years. 2100 minus 1961 will give the answer.
You are 139 years old.
(1668 months are passed.)
From 1961 to 2100 there are 139 years. If you want to learn your age in 2100 (born in 1961) your age is 139.
Let's see what will be your age if you born +1 or -1 from that date.