Sata was elected last year in his fourth attempt at the presidency, campaigning as the champion of poor Zambians to oust a party that had held power for 20 years.
His government's first budget doubled the royalties paid by copper mining companies, from 3 to 6 percent.
It also made primary health care free and lifted the tax burden from workers earning less than about $400 a month.
In July, the World Bank raised Zambia's status from a lower-income to a middle-income country, when its per capita annual national income passed the $1,006 barrier.
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