The Custom Department collects monthly trade data from every lot of imported and exported rice following the international Harmonized Commodity Description and Coding System. The data are also available on the MoC website and trader associations such as the Thai Rice Exporters Association (TREA). The Bangkok rice price, free on board, is derived from the trade data that are collected by the TREA on a weekly basis from the website. Rice stock data are collected by the MoC and TREA for their internal consumption. The monthly rice stock data are estimated by both the government and private sectors. One problem of monthly stock data is the lack of monthly rice production and utilization data, especially for production. The most recent available stock data have a one year lag.