Complex sentence: The Protocol entered into force on 18 January 2002, and as of December 2013,166 states are party to the Protocol and another 10 states have signed but not yet ratified it.
Split into simpler sentences: The Protocol entered into force on 18 January 2002. As of December 2013,166 states are party to the Protocol and another 10 states have signed but not yet ratified it.