The study I linked to earlier in this thread found the bear to be predetory in 88% of fatal black bear attacks. This studied the 59 incidents resulting in the death of one or more people by a black bear from 1900-2009.

Unfortunately as this only covers fatalities, it doesn't look at encounters where the people survived so you can't see how many total encounters there may have been over that period or how many encounters not relating in fatalities may have been with black bears exhibiting predetory behavior (such cases were ancedotally mentioned in the study, but not enumerated).

That study did add: "However, we note that an analysis of fatal attacks that occurred over a long time period (110 years) may make black bear seem more dangerous than they are, because some people may focus on the total number and ignore the long time period during which the fatal attacks occurred."

In context, that's like one fatal attack every 2 years for all of the US (Alaska & the lower 48) and Canada.