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The prediction of volume production is the basis for obtaining logging authorization and of forest management planning in managed areas in the Brazilian Amazon. Therefore, there is an increasing necessity of volumetric equations that can make increasingly precise estimates. The objective of this study was to analyze the performance of species-specific equations in relation to generic ones in Annual Production Units (APU) within a Forest Management Area (FMA) in the Amazon. A total of 29,119 trees from 43 species were inventoried, harvested, and volumetric measurements were taken, with 10% of this total being previously separated for validation and comparison of the selected equations. Due to the inherent error in visual estimation of commercial height in forest inventories, generic and specific single input equations were selected. Using volume estimates, the percent error in the prediction of revenue were calculated. The use of specific equations resulted in much more precise estimates of commercial volume. The gains in precision resulted in reduction in error in revenue prediction thus decreasing risk of economic loss. These results show that besides being statistically valid, specific equations represent the best alternative for obtaining more precise estimates of commercial volume and are therefore recommended for use.