A confounding variable is an extraneous variable that is related to your independent variable and might affect your dependent variable. In an ideal study, there will be no confounding variables.
For example, student accounts have a limit of $100 limit per day, while non-business accounts usually are limited to $500 withdrawals a day. For business accounts, the bank offers $1000 withdrawals in one day. Chase also offers customers a withdrawal limit of $1000 every 24 hours.
In October 2013, we also reported on how Chase instituted policy changes which banned international wire transfers while restricting cash activity for business customers (both deposits and withdrawals) to a $50,000 limit per statement cycle.