 First Trust Advisors LP trimmed its stake in Blackrock Muniyield Insured Fund Inc. NYSE:MYI by 7.1 in the fourth quarter, Holdings Channel reports. The firm owned 82,825 shares of the investment management companys stock after selling 6,319 shares during the quarter. First Trust Advisors LPs holdings in Blackrock Muniyield Insured Fund were worth 1,118,000 as ... 