(RNS) A Duke Divinity School report on the clergy shows that there is a shortage of pastors willing to lead small congregations.

Patricia M.Y. Chang found in her study that there is not an overall clergy shortage but rather a “problem of balance” between available clergy and pastoral vacancies.

“The number of small congregations that cannot afford a full-time or fully ordained pastor is increasing and the number of ordained pastors willing to serve in small congregations is decreasing,” she said in the report titled “Assessing the Clergy Supply in the 21st Century.”

Chang, the assistant director of Boston College’s Boisi Center for Religion and American Public Life, said the problem seems to be widespread and increasingly acute among denominations that have declining memberships.

Churches without full-time clergy are relying instead on lay pastors, part-time clergy, and pastors who are supported by either a partner’s income or retirement benefits from previous careers.

Congregations in rural areas and those with growing ethnic populations also are facing challenges in filling their pulpits.

Chang said pastors of small congregations have the advantage of more “hands-on” ministry and closer relationships with members, but those congregations have trouble meeting the economic needs of full-time clergy due to limited resources.

Findings furthermore reflect patterns within American religion where the majority of congregations have fewer than 100 regular participants but the majority of churchgoers attend medium and large congregations with more than 350 attendees.