How many cargo ships (bulk, oil, lng, lpg, container) in world over 500 ton? and how many container ships in world?

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there is NO permanent answer because everytime there is additional ship have been made and there is also ship that was get damage and not all ship was recognize and registered and monitored by an individual.
SO no one can tell, the answer you got is just an assuming.........

Dear, The speed of ship`s registration and demolition is not fast to prepare a data.
There is a regular and authantic data compiled by alphaliner.
Regards, Fawad Buzyb Shipping agencies