The unattractive truth hurts those who hate to hear it.
If there are 5 per 100 people, everyone applauds how diverse the community is.
At 5-10% there is an occasional spike in loudness, but it's usually isolated and brief.
People are usually too embarrassed to say anything, and it temporarily abates.
At 10-20%, disturbances rise dramatically. People occasionally hear loud hip-hop music from a passing vehicle, yelling, and fighting-- usually later & later at night, as an outgoing signal of rising 'diversity' in the community.
At 20-30%, the loudness & behavior is so disruptive that well-meaning families begin to stop going to certain public areas. Fights occur to establish dominance, and fights between females occur in parking lots, usually over a male.
At 30-40% minor public incidents give way to more serious crimes, and somewhere in the community the first felonies occur, targeting the elderly or defenseless.
Reaching 40-60% we see an atmosphere that is so loud, dangerous, & unpredictable that it interferes with peaceful activity. At this stage people's gut sense of "safety" in the community is eroding. Anticipating the unexpected starts to factor into simple decisions like going to the store or getting into one's car.
At 60-75% you can expect covert drug use, and concealed guns. Good and decent families are moving away. At this stage loud bass thumping from cars is now an advertisement for illegal drug sales.
Now, at 75-85%, walking down the street is a risk. We find hair-trigger, unprovoked violence, usually targeted against those of other races. Calls to 9-1-1 demonstrate slower & slower response times. Local businesses deteriorate, as does the general condition of the neighborhood. The last of the liberal, die-hard families vacate the community they have cherished for decades.
At 85-95%, the public institutions in the area (schools, libraries, etc.) slowly wither from lack of use. Consumer places (food stores, day-care centers, etc.) show graffiti & territorial gang signs, and gang membership now outweighs the number of non-gang people. Drug sales & prostitution are open and obvious. A gunshot is heard every week. All businesses which are still in operation (liquor stores, stereo wholesalers, etc.) have bars on the windows.
Once a population of 95-100% is reached, there is debris everywhere. A large number of dwellings are ruined or burned-out. At this stage, the economy of the community is nearing total collapse, and good jobs do not exist. Emergency services infrequently patrol for fear of risking officers' lives.
The name of the neighborhood is now synonymous with violence & gangs.
At this stage the spread of this condition bears characteristics similar to the unchecked spread of a virus, and adjacent communities begin to show signs of following suit
