The first round of petroleum concession bidding was announced on 13 September 1971 and 9 awarders were received altogether 22 blocks. Until 2008, 62 concessions with 80 blocks were still held, Table 2.1 illustrated for more detail, the petroleum concessions maps of Thailand illustrated in figure 2.10-2.12, petroleum production history from 1981-2008 are shown in figure 2.13-2.15.