Twelve years after cocaine addiction treatment, men who attained stable recovery - that is, were continuously abstinent for at least 5 years - reported less past-year criminal involvement, unemployment, and abuse of other substances than those who continued to abuse the drug. Among the 266 male veterans interviewed at the follow-up, more than half (51.9%) reported sustained abstinence for at least 5 years (11.2 years, on average).
Source
Hser, Y.I. et al. A 12-year follow-up of a treated cocaine-dependent sample. Journal of Substance Abuse Treatment 30(3):219-226, 2006