A warning on the health of US consumers by America’s department store is likely sending quakes through the C-suites of similar retailers. And investors in retail stocks need to pay attention because there could be aftershocks. On Tuesday, Macy’s said its second quarter credit card sales tanked 36% from the prior year to $150 million. The culprit: Bloated balances on Macy’s Citibank-powered credit card have been met with a rising interest rate environment. In turn, cash-strapped consumers — enduring an almost 32% annual percentage interest rate on the Macy’s card — haven’t been able to pay off their bills. Macy’s has opted to write off those balances. Read more at Yahoo!Finance.