Ohio Rev. Code § 145.21
The public employees retirement board shall provide for the maintenance of an individual account with each contributor showing the amount of the contributor's contributions and the interest accumulations thereon. It shall collect and keep in convenient form such data as is necessary for the preparation of the required mortality and service tables, and for an actuarial valuation of the assets and liabilities of the various funds created by this chapter. Upon the basis of the mortality and service experience of the members, contributors, retirants, and beneficiaries of the public employees retirement system, the board shall adopt from time to time such tables as are deemed necessary for valuation purposes and for determining the amount of annuities to be allowed on the basis of the contributions.
R.C. §145.21