It's been more than a month since production increased at the Toyota plant in Georgetown, Kentucky after a weeks-long parts shortage.The shortage was caused by the April earthquake and tsunami in Japan, which severed and disrupted supply chains. All of Toyota's 13 North American plants saw production drop as a result."We were fortunate that we had localized so much of our production here in the United States over the last many years. In fact, when it comes to building the Camry, the domestic content of that vehicle is over 80%," says factory spokesman Rick Hesterberg.But production has not yet returned to pre-disaster levels. Hesterberg says that's a symptom of lower demand rather than a lack of parts."If you came into our plant and toured our facility, you'd see a normal flow of operations," he says. "Every plant goes through different phases and terms of volume levels and it's all part of market demand."The plant was dark last week for routine maintenance not associated with the parts shortage.