When did ICD9 coding start?

ICD-9 was published in 1979, however is modified every year. Though before ICD-9 there was a ICD-8 published in 1973. However many systems have been developed in the past, ICD started in1948 by WHO. Classification and coding started in England with John Graunt in the 17th century though it was not what ICD-9 is today.