There was much growth in mine production under the Bourbons, with silver output increasing by over 15 million Pesos in Mexico alone. Some historians attribute this growth to the Bourbon reforms, whereas others attribute it more to the rising investments of entrepreneurs into mining during this period. For example, regarding Zacatecas, a mining region with huge turnover in mining production, historian Tandeter argues that “There the rise of the first quarter of the century can be attributed to individual entrepreneurs.” Entrepreneurial investements allowed for improvements in mining technology and lower costs.