Question: How long was Nigeria under military rule?
About the article "Nigeria", section "Democratization (1999-)".

Candidate passages:
After gaining independence in 1960 from Great Britain, Nigeria fell prey to civil war and the first of many military coups in 1966.
Democracy was briefly restored from 1979 to 1983, but for most of its independent history, Nigeria was ruled by a series of military juntas.
The last major military ruler, Gen. Sani Abacha, died suddenly in 1998.
His successor, Gen. Abdulsalami Abubakar promised a transition to democracy, and accordingly a new constitution was adopted on May 5th, 1999.
Elections were held and retired Gen. Olusegun Obasanjo, who had previously governed Nigeria as a military ruler, was elected the new president.
The end of military rule brought about a new era of regular elections as well as the return of civil liberties, free press and an end to arbitrary arrests and torture, although human rights violations still occur regularly.
Nigeria also began a long campaign against the bureaucratic and military corruption that had paralysed its economy and severely tarnished its international reputation.  
Nigeria today is seemingly democratic with there having been no military coups since 1999, however the decades under military rule have had a resounding impact on the nation with all today’s 36 states created by the military and there still being a considerable military influence evident. 
The 1993 constitution was intended to see the return of democratic rule to Nigeria with the establishment of a Third Republic, but was never fully implemented, and the military resumed power until 1999 
Hugh Trenchard saw service in Nigeria from 1903 to 1910 where he was involved in efforts to bring the interior under settled British rule and quell inter-tribal violence.
During his time in West Africa, Trenchard commanded the Southern Nigeria Regiment for several years and was promoted to lieutenant colonel. 
The Ibibio people are located in Southeastern Nigeria also known as Coastal Southeastern Nigeria.
Prior to the existence of Nigeria as a Nation, the Ibibio people were self-governed.
The Ibibio people became a part of the Eastern Nigeria of Nigeria under British colonial rule.
During the Nigerian Civil War, the Eastern region was split into three states.
Southeastern State of Nigeria was where the Ibibios were located, one of the original twelve states of Nigeria) after Nigerian independence.
The Efik, Anaang, Oron, Eket and their brothers and sisters of the Ogoja District, were also in the Southeastern State.
The state (Southeastern State) was later renamed Cross Rivers State.
Again in the year 1987, by a Military Decree No.24 promulgated that same year, Akwa Ibom State was carved out of the then Cross Rivers State as a separate State on her own on 23 September 1987.
Cross Rivers State remains as one of neighboring States.
Southwestern Cameroon was a part of present Cross River State and Akwa Ibom State of Nigeria.
During the then Eastern Region of Nigeria it got partitioned into Cameroon in a 1961 plebiscite.
This resulted in the Ibibio, Efik, and Annang being divided between Nigeria and Cameroon.
However, the leadership of the Northern Region of Nigeria was able to keep "Northwestern section" during the plebiscite that is now today's Nigerian Adamawa and Taraba states.