Merchants are barred by their credit agreements from passing these expenses straightforwardly to credit card customers, or from setting a base transaction amount never again disallowed in the United States, United Kingdom or Australia. Finally, credit cards decrease the back office cost of preparing checks/cash and transporting them to the bank. The affectation can be solid because the merchant's charge is a percentage of the sale value, which has a disproportionate impact on the profitability of organizations that have predominantly credit card transactions, except if compensated at by raising costs generally. In the United States in 2008 credit card companies gathered a total of $48 billion in interchange charges, or an average of $427 per family, with an average expense rate of about 2% per transaction. Much of the time, cards are considerably more secure than cash, because they discourage robbery by the merchant's workers and diminish the amount of cash on the premises.