2020, Tsai was re-elected and the ruling DPP won a majority in the simultaneous legislative election. The 2020 Democracy Index published by London-based Economist Intelligence Unit upgraded Taiwan from a "flawed democracy" to a "full democracy", raising it from the 31st place previously to the 11th, the highest in Asia. Geography The land controlled by the ROC consists of 168 islands with a combined area of . The main island, known historically as Formosa, makes up 99 percent of this area, measuring and lying some across the Taiwan Strait from the southeastern coast of mainland China. The East China Sea lies to its north, the Philippine Sea to its east, the Luzon Strait directly to its south and the South China Sea to its southwest. Smaller islands include the Penghu Islands in the Taiwan Strait, the Kinmen, Matsu and Wuqiu islands near the Chinese coast, and some of the South China Sea islands. The main island is a tilted fault block, characterized by the contrast between the eastern two-thirds, consisting mostly of five rugged mountain ranges parallel to the east coast, and the flat to gently rolling plains of the western third, where the majority of Taiwan's population reside. There are several peaks over 3,500 metres, the highest being Yu Shan at , making Taiwan the world's fourth-highest island. The tectonic boundary that formed these ranges is still active, and the island experiences many earthquakes, a few of them highly destructive. There are also many active submarine volcanoes in the Taiwan Strait. Taiwan contains four terrestrial ecoregions: Jian Nan subtropical evergreen forests, South China Sea Islands, South Taiwan monsoon rain forests, and Taiwan subtropical evergreen forests. The eastern mountains are heavily forested and home to a diverse range of wildlife, while land use in the western and northern lowlands is intensive. The country had a 2019 Forest Landscape Integrity Index mean score of 6.38/10, ranking it 76th globally out of 172 countries. Climate Taiwan lies on the Tropic of Cancer, and its general climate is marine tropical. The northern and central regions are subtropical, whereas the south is tropical and the mountainous regions are temperate. The average rainfall is per year for the island proper; the rainy season is concurrent with the onset of the summer East Asian Monsoon in May and June. The entire island experiences hot, humid weather from June through September. Typhoons are most common in July,