The main commodities exported from Taiwan to the mainland are electromechanical products, optical clock and watch medical equipment, chemical products and plastics and rubber, with export value of US$30.84 billion, US$10.49 billion, US$7.84 billion and US$6.80 billion respectively in 2015, accounting for 46.0%, 15.6%, 11.7% and 10.1% of the total export value to the mainland, a year-on-year decline of 7.8%, 20.5%, 21.3% and 17.1% respectively.