Results and data associated with Lark et al. 2021: Accuracy, Bias, and Improvements in Mapping Crops and Cropland across the United States Using the USDA Cropland Data Layer. Accuracy data for original, non-aggregated CDL classes are located in the following files: 'NASS_CDL_National_20XX_original_accuracy' files contain each year's data and calculation results for original, non-aggregated CDL classes 'Nationwide_original_CDL_accuracy_2008to2017_w_ref_area' is the nationwide reference producers and users accuracy for average crops, average non-crops, and the individual classes for all years. 'State_level_annual_ref_acreage' is the percent of reference acreage for both crops and non-crops by each state and national total for all years, used for the area-weighting calculations. Accuracy data for aggregated CDL classes are located in the following files: 'NASS_CDL_National_20XX_superclass_accuracy' files contain tables for each year that include the total and reference acreage of the datasets, the users and producers superclass accuracies for the individual classes, and consolidated crop and consolidated non-crop accuracy, as well as the raw and intermediate data used to calculate these results. 'Annual_CDL_superclass_accuracy_by_state_crop_noncrop' contains the average crop and non-crop superclass accuracies (i.e. the consolidated crop and consolidated non-crop accuracy) for the nation and for the individual states for all years. Citation: Lark TJ, Schelly IH, Gibbs HK. Accuracy, Bias, and Improvements in Mapping Crops and Cropland across the United States Using the USDA Cropland Data Layer. Remote Sensing. 2021; 13(5):968. https://doi.org/10.3390/rs13050968