Happy New Year.
It's also worth noting that your true, or inward sign is determined by the time of day you were born. This was in part due to how Asians used to run on a twelve-hour clock.
11:00 P.M. - 1:00 A.M. (Rat)
1:00 A.M. - 3:00 A.M. (Ox)
3:00 A.M. - 5:00 A.M. (Tiger)
5:00 A.M. - 7:00 A.M. (Rabbit)
7:00 A.M. - 9:00 A.M. (Dragon)
9:00 A.M. - 11:00 A.M. (Snake)
11:00 A.M. - 1:00 P.M. (Horse)
1:00 P.M. - 3:00 P.M. (Goat)
3:00 P.M. - 5:00 P.M. (Monkey)
5:00 P.M. - 7:00 P.M. (Rooster)
7:00 P.M. - 9:00 P.M. (Dog)
9:00 P.M. - 11:00 P.M. (Pig)
There's more that goes into that though, such as time zone, daylight savings time, and even longitude.