DEFINITION OF ‘INVESTMENT GRADE’
A rating that indicates that a municipal or corporate bond has a relatively low risk of default. Bond rating firms, such as Standard & Poor’s, use different designations consisting of upper- and lower-case letters ‘A’ and ‘B’ to identify a bond’s credit quality rating.
‘AA’ (high credit quality) and ‘A’ and ‘BBB’ (medium credit quality) are considered investment grade. Credit ratings for bonds below these designations (‘BB’, ‘B’, ‘CCC’, etc.) are considered low credit quality, and are commonly referred to as “junk bonds”.
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