I have a spreadsheet with 3 columns (the first one has a date like '20100224', the second one a text string like 'european union' and the third one a numeric string with a value like '3') and 250'000 rows. Is there a way to aggregate and reorganize these data in such a way that I get sthg like this - i.e. with all dates aggregated into years, and those years then displayed vertically in declining order and horizontally next to each other first a column with the top text string for year x and in the next column the sum of all the values for that text string for that year; and then in the next two columns the same but then for year x+1, etc.?