The first production of tea is traced back to 1717 Shui Sha Lan in Nantou, Taiwan. Oolong grown in Taiwan account for 20% of all oolong produced throughout the world. Dong Ding was the first oolong tea documented processed. Taiwan's government has invested heavily into research that accounts much for their quality development. For instance, in the 1990's, Ruby #18, the hybrid Assam variety from Burma was bred with a sinensis variety claimed to be indigenous to Taiwan which is typically processed into a black tea.