How about the duration of patent protection in China?

The duration of patent right for inventions is twenty years, the duration of patent right for utility models and patent right for designs is ten years, counted from the date of filing, but basing on the rules of 39 and 40 of the Patent Law, the patent right for invention, utility model and design shall come into effect as of the date of the announcement. Therefore, the above-mentioned duration is just a calculating formula, but not exactly same as the years mentioned above.