Original sentence: Also, decades are almost always considered as starting with the "0" year and named accordingly ("1960s", etc.Common usage sometimes regards it as lasting from 1900 to 1999.One advanced by Stephen Jay Gould is that the first decade had only nine years, thus contradicting the definition of decade equaled 10 years
Edited sentence: Common usage sometimes regards it as lasting from 1900 to 1999, but this is incorrect since counting of calendar years begins with the year 1.Decades are almost always considered as starting with the "0" year and named accordingly ("1960s", etc.He claimed that the first decade had only nine years, thus contradicting the definition of decade equaled 10 years.One was advanced, erroneously, by Stephen Jay Gould