Card Stats show your data on your card and campaigns that link to your card.
Select the card that you want to see the stats for:
You can determine the time period that you would like to see your "General" or Card sends and views data:
You can also see the "Card Ratio" to see the in depth stats breakdown of your general sends and opens:
Viewer Clicks will tell you what links or buttons that your recipients have selected:
Lastly, "Campaigns" on your card will tell you how many clicks you had for each campaign that you have linked to this card: