Nice graphs, looks like the late 70's early 80's were some wild times. I quickly tried to find historical population data but only found the data in the below link.
Laconia still looks mostly white to me, 96.79% (15,855) of the total 16,411 in the 2000 census. There is 90 black, 120 asian, 162 hispanic,68 american indian and alaskan native, and a few others.
Crime looks like it has increased a little, but judging from the statewide trends its still probably a lot better than it was in the late 70's.
What does this all mean? I don't know.
If I were to just look at the stats and didn't know better I would say that every resident was visited by the police at least once in a year, 4000 of them committed criminal offenses and 2000 of them were arrested. Looking at the original data from the link it looks like traffic stops went way up in 2003 from 4700 in 2002 to 7100 in 2003 better be careful when driving in Laconia.
http://laconia.areaconnect.com/statistics.htm