Americans love to send greeting cards. For instance, over 4 million birthday cards are sent out in this country every day. Around Valentine’s Day last year, over 900 million cards were mailed. And close to 3 billion holiday greeting cards were sent out during the Christmas season.

Subject: Greeting cards

Main idea: Americans love to send and receive greeting cards for various occasions throughout the year.

Supporting details:
- Over 4 million birthday cards are sent out in the United States every day
- Around Valentine's Day, over 900 million cards were mailed
- Close to 3 billion holiday greeting cards were sent out during the Christmas season