This excel file includes the following variables: - *ID* - *Age* - *Gender* - *nation* - 50 addition items of the format *a**xx**plus*xx** with *a* standing for addition, followed by the ***first digit*** *plus* the ***second digit*** - 50 subtraction items of the format *s**xx**minus**xx*** with *s* standing for subtraction, followed by the ***first digit*** *minus* the ***second digit*** - 50 multiplication items of the format *m**xx**times**xx*** with *m* standing for multiplication, followed by the ***first digit*** *times* the ***second digit*** - 50 division items of the format *d**xx**by**xx*** with *d* standing for division, followed by the ***first digit*** *by* the ***second digit*** All arithmetic items are listed in the order as they appear in our speeded arithmetic lists. Please enter the exact answer given by the participant. Whether the answer was right or wrong will be automatically analysed with our R script "Math4Speed_preprocessing.R" provided in the component *Material*.