Columbia and the Yukon, Canada (encompassing the Atlantic provinces and Quebec), Ontario, and Rupert's Land (encompassing the prairie provinces, Nunavut, the Northwest Territories, and portions of Ontario). Within the provinces are 29 dioceses and one grouping of churches in British Columbia that functions equivalently to a diocese. Each province has its own archbishop, known as the Metropolitan, and each diocese has a bishop, although there are no metropolitical dioceses (or archdioceses) as such; a metropolitan is styled "Archbishop of [his or her own diocese], and Metropolitan of [the ecclesiastical province]." As with other churches in the Anglican tradition, each diocese is divided up into geographical regions called parishes, where certain authority resides in the rector or priest-in-charge (as laid out in the induction service, the ordinal, and the cleric's licence) and in the parish council (or vestry) as defined in diocesan canons. The legal relationship between a parish and its diocese and between a parish and its synod varies around the country and even within dioceses depending in part on when each was established. Both dioceses and provinces hold synods, usually annually, consisting of the active diocesan clergy and lay delegates elected by parish churches. Diocesan synods elect lay and clergy delegates to provincial synod. On the diocesan level, there are effectively two houses instead of three – clergy and laity – with the diocesan bishop required to give assent to motions passed by synod. Between 1995 and 1997 over 500 parishes closed. Of all the mainline churches in Canada, the Anglican Church of Canada has the most precipitous drop in members; according to its own records, a reduction of 10% in membership occurs annually. Ecumenical relations The ACC is a member of the World Council of Churches and Archbishop Ted Scott was a president of that body; the ACC has been an active participant in the Canadian Council of Churches from its establishment in 1944. Through the 1960s the ACC was involved in talks with the United Church of Canada and the Disciples of Christ with a view to institutional union, in the course of which a comprehensive Plan of Union was formulated and a joint Anglican-United Church hymnal produced in 1971. Ultimately such talks foundered when the Houses of Laity and Clergy voted in favour of union but the House of Bishops vetoed it, largely due to concerns over the maintenance of the apostolic succession of the episcopacy.