There has been a trend of increasing market weight for decades, and it is expected to continue due to supplier demand and producer benefit.  The benefit to the producer is that as weight increases the cost per additional kg decreases; however, space may be a limiting factor. Building new facilities, or additions to existing facilities is an expensive option to provide space. Two more cost efficient ways to provide sufficient space would be to reduce breeding, or sell excess weanlings. Even though fewer market pigs will be produced, the net profit per kg will increase.