one - year , ▁two - year , ▁five - year ▁and ▁so ▁on ) ▁was ▁thought ▁of ▁as ▁a ▁separate ▁market ▁until ▁the ▁mid - 1 9 7 0 s ▁when ▁trad ers ▁at ▁Sal omon ▁Brothers ▁began ▁drawing ▁a ▁curve ▁through ▁their ▁yields . ▁ ▁This ▁innov ation ▁- ▁the ▁yield ▁curve ▁- ▁transformed ▁the ▁way ▁b onds ▁were ▁both ▁pr iced ▁and ▁trad ed ▁and ▁p aved ▁the ▁way ▁for ▁quant itative ▁fin ance ▁to ▁fl our ish . ▁ ▁Starting ▁in ▁the ▁late ▁ 1 9 7 0 s , ▁non - in vest ment ▁grade ▁public ▁companies ▁were ▁allowed ▁to ▁issue ▁corpor ate ▁deb t . ▁ ▁The ▁next ▁innov ation ▁was ▁the ▁advent ▁of ▁Der iv atives ▁in ▁the ▁ 1 9 8 0 s ▁and ▁on wards , ▁which ▁saw ▁the ▁creation ▁of ▁Coll ater al ized ▁deb t ▁oblig ations , ▁Res ident ial ▁mort g age - back ed ▁se cur ities ▁and ▁the ▁advent ▁of ▁the ▁Struct ured ▁products ▁industry . ▁ ▁See ▁also ▁ ▁Bond ▁Bond ▁market ▁index ▁Bond ▁valu ation ▁Corpor ate ▁bond ▁De ferred ▁finan cing ▁costs ▁Government ▁bond ▁Interest ▁rate ▁risk ▁Primary ▁market ▁Second ary ▁market ▁Bul let ▁strategy ▁Bar bell ▁strategy ▁War ▁Bond ▁Specific : ▁US ▁Sav ings ▁B onds ▁Foreign ▁exchange ▁res erves ▁of ▁the ▁People ' s ▁Republic ▁of ▁China ▁ ▁References ▁ ▁Category : Fixed ▁income ▁Category : B ond ▁market ▁Category : Fin an cial ▁mark ets <0x0A> </s> ▁m t - SN P