Even staid custody banks are finding unpleasant ways to surprise: shares in State Street lost almost 60% of their value on Tuesday as it announced hefty losses on bond investments, among other things.

• 甚至连稳健的托管类银行也要找些让人不快的惊讶：周二，美国道富银行股价下跌近60%25，原因是公司公告了在债券投资其他领域出现巨幅损失。