According to a recent study of 17 primary care clinics using Electronic Health Record (EHR) systems

it took an average of 10 months for the clinics to recover their EHR investments.

Source: "Return on Investment in Electronic Health Records in Primary Care Practices: A Mixed-Methods Study," JMIR Medical Informatics, September 29, 2014, http://medinform.jmir.org/2014/2/e25/