To solve this question we have to make deduct these 2 years. 2099 minus 1990 will give the answer.
You are 109 years old.
(1308 months are passed.)
From 1990 to 2099 there are 109 years. If you want to learn your age in 2099 (born in 1990) your age is 109.
Let's see what will be your age if you born +1 or -1 from that date.