History of Bolivia to 1809 reduction in silver output. After 1700 only small amounts of bullion from Upper Peru were shipped to Spain. Kings from the Bourbon Dynasty in Spain tried to reform the colonial economy in the mid-eighteenth century by reviving mining. The Spanish crown provided the financial support necessary to develop deeper shafts, and in 1736 it agreed to lower the tax rate from 20 to 10 percent of the total output. The crown also helped create a minerals purchasing bank, the Banco de San Carlos in 1751 and subsidized the price of mercury to local mines. The foundation of an academy of
Lê dynasty system, including the civil service and laws. Their long-lasting rule was attributed to the popularity of the early emperors. Lê Lợi's liberation of the country from 20 years of Ming rule and Lê Thánh Tông's bringing the country into a golden age was well-remembered by the people. Even when restored Lê emperors' rule was marked by civil strife and constant peasant uprisings, few dared to openly challenge their power, at least in name, for fear of losing popular support. When the Mạc dynasty tried to do so, they were not successful and were considered as usurpers and not recorded in