In February Vedanta Resources, the company that runs the Konkola Copper Mines, agreed to raise wages for all its workers by 11%. This decision follows strikes over wages in November 2009, which led to an estimated 40% drop in the mine's output in the last quarter of 2009, and renewed threats that workers would go on strike again if they were not given above-inflation pay rises. The pay increase was negotiated by the Mine Workers' Union of Zambia (MUZ). The MUZ also recently negotiated a 22% pay increase for employees at the Lumwana mine, owned by Equinox Minerals, and a 10.5% increase for workers at the Mopani Copper Mine, owned by a Swiss firm, Glencore International, in both cases averting the possibility of strikes. The pay rises will help to maintain stability in the Copperbelt-where unions have been prone to strikes over pay in the past (September 2007, The domestic economy)-and to sustain the recent recovery in copper production.