How long should a couple live together before it is considered a common law marriage?

Max Power asked:


I am speaking about couple living together and not married.

A) one year
B) three years
C) five years
D) ten years
E) never

Let’s just assume no children are involved.

I ask because people say they are afraid of losing half if not more after a divorce. Yet the laws for common marriage basically can do the same thing. Do you agree with common law marriages?
Zin- I asked for your opinion not what the New York law states. Thanks.

marriage law