To solve this question we have to make deduct these 2 years. 2099 minus 1959 will give the answer.
You are 140 years old.
(1680 months are passed.)
From 1959 to 2099 there are 140 years. If you want to learn your age in 2099 (born in 1959) your age is 140.
Let's see what will be your age if you born +1 or -1 from that date.