The value of land sales in 50 major cities in China rose by nearly 50 percent compared to the previous year, to over 1 trillion yuan in the first six months, data from a research center affiliated to real estate firm Centaline Group showed. The sales included over 200 "land kings," a reference to a plot sold for a record-breaking price. While sales at a high premium helped fill local government coffers, rising land prices have raised concerns among industry analysts because it can push up housing prices, adding to the woes of property developers stuck with large inventories of unsold homes.