Shariah rules about the person sacrificing the animal
Sacrifice of an animal is Compulsory (Wajib) on every adult and sane Muslim who is the owner of prescribed limit of wealth as specified under the Shariah. Unlike Zakaat, there is no rule here that the wealth should be of an increasing nature or that a year must have passed on it. However, these rules are there for Zakaat.
That the person making the sacrifice should have some prescribed wealth is mentioned in the Hadith:
Hadhrat Abu Hurairah (May Allah be well pleased with him) narrates that the Holy Prophet (Sallallahu alaihi wa sallam) said: The one who is able to sacrifice an animal, but does not do so, should never come near our Eidgah (place where Salaat Ul Eid is offered).
(Sunan Ibn Majah, Hadith No. 3242)