How many new hires can one onboarding professional effectively bring on in a 12 month period...assuming the onboarding person does everything from preparing the job descriptions, to postings, to applicant review, to interviews, to orientation, to fil

How many new hires can one onboarding professional effectively bring on in a 12 month period...assuming the onboarding person does everything from preparing the job descriptions, to postings, to applicant review, to interviews, to orientation, to file maintenance, etc. of each new employee?