FILE AGGRE <Survo_data_file>,<new_aggregated_file> combines observations in a Survo data file according to values of a selected grouping variable. Only variables activated by 'A' will be processed. The observations can be weighted by a selected variable activated by 'W'. Aggregation is controlled by an extra specification AGGRE having the form AGGRE=<grouping variable>,<SUM or MEAN>. The observations with the same value in <grouping variable> are combined either by summing the values of variables (SUM) or by computing their mean values (MEAN). If missing values occur in any active variable, the observation in question is left out. The aggregated observations are saved in a new Survo data file with the same structure as the original data file. If <new_aggregated_file> already exists, it is overwritten. To save the frequencies (or sums of weights, if 'W' variable exists), a specification FREQ=<name_of_variable> can be entered. This variable will be automatically created for the new aggregated file. Example: MASK=--W--AAA-AAA--- / 'Popul' is weight variable FILE AGGRE FINLAND,PROVS AGGRE=Province,MEAN FREQ=Popul computes weighted means of 6 variables in provinces of Finland. The aggregated data set is saved in a new data file PROVS. Total population of each province will appear as 'Popul' in PROVS. D = More information on data management