How many years was Ted Bundy killing people?

I guess it would depend on which victims you think he killed. There is compelling circumstantial evidence that Bundy killed for the first time when he was 14 years old. Ann Marie Burr, an 8 year old Tacoma girl went missing from her home in 1961. Not only did Bundy know Burr (she took piano lessons from Bundy's uncle) but the victim's father spotted Bundy in the neighborhood the morning of her disappearence. Recently law enforcement were hoping to close this old case with DNA evidence but were disappointed with the results. There was not enough DNA for an accurate profile. This does not clear Bundy as Burr's killer, just that there was not enough to prove she was his first victim.

Bundy began his crimes in earnest in 1974 and was finally arrested for the final time in June 1978 in Florida approximately 1 week after he killed 12 year old Kimberly Leach. If Burr was Bundy's first victim his killing career spanned from 1961 until his arrest in Florida in 1978. The bulk of his murders were between the years 1974 and 1978.