BANK OF AMERICA reported net income of $6.92 billion for the first quarter. / BLOOMBERG FILE PHOTO/RON ANTONELLI
NEW YORK - Bank of America Corp. hit a new milestone in its years-long effort to get costs under control. First-quarter expenses totaled about 60 percent of revenue, the best ratio in more than five years. That helped push profit above analysts’ estimates, and corporate tax cuts spurred earnings to a record. Net interest income got…