Depends on the month, but about 44 years old.
2017 - 1973 = 44
People born in 1973 will turn 44 in 2017.
2017 − 1998 = 19 years old
2017 − 1998 = 19 years old
3983
You would turn 661 in 2017.
You would now (24 July 2017) be 33 years old.
Where you were born is irrelevant. In 2017 (now) you would be 64 years old if you have had your birthday this year, otherwise you are 63.
15th birthday in 2017
36 + 17 = 5353rd birthday is in 2017
You would celebrate your 16thh birthday during 2017
2017 − 1961 = 56 years old on the person's birthday in 2017.