$6,451,881,056
Chargeback Info
Here are some useful links where you can get unbiased information about chargebacks:
http://www.merchantaccounts4free.com/glossary.php
http://www.investopedia.com/terms/c/chargeback.asp
http://en.wikipedia.org/wiki/Chargeback
https://www.wellsfargo.com/biz/help/merchant/faqs/chargeback
http://www.websitepublisher.net/article/chargebacks/