It lends at a 4% interest rate with a 25-year repayment period, including a five-year grace period. The loans can be used for concessional loan operations with long and short term maturity. Management and control The AfDB is controlled by a Board of Executive Directors, made up of representatives of its member countries. The voting power on the Board is split according to the size of each member's share, currently 60%-40% between African (or "regional") countries and “non-regional” member countries (“donors”). The largest African Development Bank shareholder is Nigeria with nearly 9 percent of the vote. All member countries of the AfDB are represented on the AfDB Board of Executive Directors. Dr. Akinwumi Ayodeji Adesina is the 8th elected President of the African Development Bank Group, having taken the oath of office on September 1, 2015. He chairs the Boards of both the African Development Bank and the African Development Fund. Dr. Adesina served as Nigeria's Minister of Agriculture and Rural Development from 2011 to 2015. Member governments are officially represented at the AfDB by their Minister of Finance, Planning or Cooperation who sits on the AfDB Board of Governors. The AfDB Governors meet once a year (at the Annual Meetings of the AfDB each May) to take major decisions about the institution's leadership, strategic directions and governing bodies. The Governors typically appoint a representative from their country to serve in the offices of the AfDB's Board of Executive Directors. Day-to-day decisions about which loans and grants should be approved and what policies should guide the AfDB's work are taken by the Board of Executive Directors. Each member country is represented on the Board, but their voting power and influence differs depending on the amount of money they contribute to the AfDB. In June 2020 the board of the AfDB agreed to a review of Adesina's management of the bank. Adesina is up for reelection in August 2020. Adesina was reelected unanimously for a second five-year term on August 27, 2020 Unit of Account The African Development Bank uses a Unit of Account which is registered as ISO 4217, whose standard currency code is . It is not exchanged directly by individuals, it is used for accounting between state members. Functions The primary function of AfDB is making loans and equity investments for the socio-economic advancement of the RMC. Second, the bank provides technical assistance for development projects and programs.