Sorry to digress slightly but if you raised two pigs over the space of a year and slaughtered them in the autumn how much meat would you get and how long would it feed a family of four for. Or are their too many variables to answer that properly?
At about 6 months old, you will get in the region of 160 lb of meat (bone in) per pig. As to how long it lasts - depends on how often you want to eat pork or bacon.