Methods, systems, apparatus, and articles of manufacture to generate corrected projection data for stores of a retailer are disclosed. An example apparatus to reduce projection errors associated with retail register devices includes a receipt data analyzer to retrieve transaction code values associated with receipts generated by the retail register devices, identify a direction change in a first subset of the retrieved transaction code values, and verify a register reset occurrence based on values associated with a second subset of the retrieved transaction code values, and a projection calculator to reduce retail sales projection error by calculating a transaction count based on the retrieved receipts and transaction code values.