You need to call the clerk of the court to get your answer becasue they are responsible for the entries in these types of records and can tell you exactly what it means.I could mean a variety of things. It could simply be a typo or update in the system which accidentally changed the number.  It could mean the bond is no longer outstanding because it has been posted.  It could also mean that the bond amount has been reduced. So... call the clerk, and get the actual interpretation of the entry.