I'm looking to concatenate data in a certain way and I don't know how to do it. I have this data set on trading card sales. The way the CSV is organized each row is a different sales point on different dates but sorted by card. For example, there will be 1 row for the sale of a card and the next row will be the sale of the same card on a different date. I would like to be able to filter the data by summary statistics on all of the sales of a specific card. Filtering out cards with fewer sales and such. I was thinking "group_by" but it's not really working. I've included a screenshot of the head() of the data. Any help would be much appreciated.