In 2017, there were 206.7 million TEUs (twenty foot equivalent unit) transported by shipping lines on the seas in the world. In that same year, the global container throughput at ports was 743.4 million TEUs at all the ports of the world.
If you want to know more, please go here. This data was sourced from the book Transportation and the Belt and Road Initiative, in which more data as well as the original primary sources of the data are available.