bond trading vs bond-trading activity

bond trading and bond-trading activity both are nouns.

Word	Noun	Adjective	Verb	Adverb
bond trading	Yes	No	No	No
bond-trading activity	Yes	No	No	No

As nouns, bond trading and bond-trading activity are synonyms defined as:

bond trading and bond-trading activity: trading in bonds (usually by a broker on the floor of an exchange)

bond trading (noun)	bond-trading activity (noun)
trading in bonds (usually by a broker on the floor of an exchange)	trading in bonds (usually by a broker on the floor of an exchange)