viewed Mwanawasa's rule as a great improvement over Chiluba's. Following Mwanawasa's death in August 2008, Zambian vice-president Rupiah Banda succeeded him to the office of president, to be held as a temporary position until the emergency election on October 30, 2008. Banda won by a narrow margin over opposition leader Michael Sata, to complete the remainder of Mwanawasa's term. 2011 elections Rupiah Banda lost re-election in the 2011 Presidential and Parliamentary elections to Michael Sata of the Patriotic Front bringing an end to a total of 20 years rule by three presidents from the MMD. 2015–present Edgar Chagwa Lungu was sworn in as president of Zambia on January 25, 2015, succeeding acting-president Guy Scott who briefly held the office after the passing of Michael Chiluyfa Sata. Lungu's presidency has thus far been criticised for failing to halt the depreciating Kwacha. There have also been unsubstantiated reports of Lungu's alleged alcoholism, stemming from a reported physical collapse early in his presidency. The economic challenges facing Zambia, in particular the depreciating Kwacha, have been attributed to the global fall of commodity prices. Zambia derives over 90% of its export earnings from a single commodity, copper, which has lost about 45% of its value on the international commodity market. On 5 January 2016, Lungu successfully concluded long-standing constitutional issues when he assented to the 2015 Constitutional Amendment Bill. This bill is the result of extensive work begun during the Mwanawasa era (The Mwanakatwe Commission) and continued by the Michael Chilufya Sata appointed Technical Committee. As justice minister, Lungu had previously presented the draft constitution to parliament, where it was subsequently decided that non-contentious issues will be debated in parliament and contentious issues will be subject to a referendum. In the August 2016 Zambian general election, President Edgar Lungu won re-election narrowly in the first round of the election. The opposition had allegations of fraud and the governing Patriotic Front (PF) rejected the allegations made by opposition UPND party. However, in 2020 the Parliament through the office of the justice minister (Given Lubinda) proposed a bill called Bill 10, which was rejected in Parliament on its third reading. In the 2021 general elections, characterised by a 70% voter turnout, Hakainde Hichilema won 59% of the vote, with his closest rival, incumbent president Edgar Chagwa Lungu, receiving 39% of the vote. On 16 August Edgar Lungu conceded in a TV statement, sending a letter and