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Violent Crime: Is Ypsi up or down from the 70s? (The data suggest down.)

With 3 days left to the election, Ypsilanti’s claws are out over on The Facebook, with one resident’s question of how conflicts of interest are defined and dealt with diverging into an argument about whether or not Ypsi is better today than in the ’70s.  (“Are you better off than 4 years ago?” is for the amateurs in Washington–this town prefers to argue in 40-year increments.)

A sample, redacted for neighborliness:

Ypsi: shouting about the '70s

Ypsi: shouting about the ’70s

At least one of these points of contention is fairly easily tackled.  “We had less violent crime [in 1979 than today]”–oh?

The FBI’s Uniform Crime Reporting database has its problems and needs heavy caveating (as they themselves explain), but it has its uses, and comparing trends over time is pretty fair.  They provide breakdowns of violent and property crimes, as well as crime rates in crimes-per-100,000-residents.  For local units, they only go back as far as 1985; for states they go to 1960, but that’s probably good enough for our purposes.  I pulled the “Violent Crime Rate” stat for Ypsi for 1985-2012 (most recent available) for same time period for Ann Arbor (for college town and local comparison), and for the 1960-2012 period for Michigan. (I used “rates” rather than total numbers to control for population change over time.) I then normalized it all to show relative trends over time–for each of these communities, how did past crime rates compare to today’s crime rates?  Graph as so:

A2, Ypsi, Michigan violent crime rates over time, normalized to 2012 violent crime rate = 1.

A2, Ypsi, Michigan violent crime rates over time, normalized to 2012 violent crime rate = 1.


It’s pretty clear from this that Ypsilanti, Ann Arbor, and Michigan all have  lower violent crime rates today (well, 2012) than they did in 1985–Ypsi’s current rate is half what it was 30 years ago, and Ann Arbor’s 1/3.  Also, both of those communities track the overall Michigan rate in broad strokes, though more exaggerated and spikier (because of the smaller samples): if we assume that tracking of state trends extends further back, we can estimate that Ypsi’s violent crime rate throughout the 70s was 50% or so higher than in 2012.

My conclusion: at least in violent crime rates, Ypsi’s clearly a lot better off than it was in the ’80s and ’90s, and probably significantly better off than it was in the ’70s.

EDIT 3 Nov. 2014: Okay, so presenting things as ratios of present (2012) rates seems to have confused people, with multiple people on Facebook taking this to mean A2’s violent crime rates are or have been higher than Ypsi’s.  That’s not the case– for most of the 1985-2012 time period, the total (population adjusted) violent crime rate in Ypsi has been 3x Ann Arbor’s, or more.  What the graph above shows is relative rate of change: Ann Arbor’s crime rate has dropped faster than Ypsilanti’s, and Ypsi’s has dropped faster than Michigan or national averages, over the past 30 years.

Here’s another version of the graph that may (or may not!) clarify that, using 1985 as the “100% point.”  The intent in presenting some year as a baseline / 100% point was to focus on change over time, in this case to address the concern that “Ypsi’s crime has dropped [only] because the national crime rate has dropped,” to show, nope, Ypsi’s crime rate is falling faster than national or state trends alone would suggest.


Diapering: earth destroyer, or crazy hippie?

Overall, our parenting is somewhere in the range of a 7 on the crappy crunchy scale, with some dips into the 2 range. (Yep, I’ll wait….okay, back now?)

Diapers are one of the both-ends-of-the-scale things.  Our primary diaper is the cloth/synthetic BumGenius FreeTime All-in-One, which, yes, costs $20 per diaper.  At night, though, we go Huggies Overnights disposables.  Cloth dipes first:

Cloth diapers have come a loooong way from the absorbant squares that you hand-fold and attach with safety pins that I and my siblings were clad in. These guys are high-tech wicking fleece numbers with multiple sizing options in 2 dimensions: we’ve been using our set since they were about 8 weeks and 8 pounds old to now, going on a year and 25 pounds old. (For the first 8 weeks, we rented a set of newborn-sized diapers from our friendly neighborhood diaper shop, Ann Arbor’s Little Seedling.)

They’re pretty darned easy to use–there’s definitely some practice bias, but we both find them easier to put on a squirming baby than the fussy little tabs on disposables–and the long-run cost/benefit is crazy good.  Even if you don’t get a bulk discount, that $20 gets you a diaper that you use about once every 36-48 hours. For us, at 9.5 months of use so far, that means we’ve used each diaper between 140-190 times so far.

At the low end of that scale, that means each diaper would have cost us 14.3 cents per use so far.  At the high end, and at Little Seedling’s bulk pricing, that cost would be about 9.4 cents per use.  If we use them until the kids are two, that cost per use ends up in the 4-6 cents per use range.

By comparison, disposable diapers are in the range of about 20 cents per diaper. If we used exclusively disposables, at our typical rate of usage, that’d be somewhere in the $2,500 range over two years.  Our set of 30 cloth diapers, plus the rental of the set of newborn diapers: about $800. Yes, there are costs to washing them and drying them (we gave up our clothesline once the dog started turning all the clean laundry on it into toys), but the 2-year savings on purchase cost of cloth diapers are enough to cover the cost of a brand-new high-efficiency washer and dryer.

There’s also a practical benefit to the reusables: it’s quite reasonable to receive a 2-year supply of cloth diapers and wipes at a baby shower, because once you’re using them, you don’t need storage space for the others, because they’re the same diapers over and over again.  Even if your friends and family wanted to give you $2500 worth of disposables at your shower, you’d be left renting a storage locker to hold them all.

If you want to talk environmental benefits, the disposable diaper industry claims no significant difference (surprise!), while the cloth diaper trade group claims those life cycle analyses are flawed, comparing the best case disposables to the worst case cloth diapers.  Fortunately, I find the practical and financial benefits of cloth diapering to be enough that it doesn’t matter if there’s zero environmental benefit.

Now, as I mentioned, we do use disposables at night.  There are certainly benefits to those chemical super-absorbing agents in disposable dipes–like letting the kiddos sleeping for 10-11 hours straight without needing a change. So using 1 disposable diaper, per kid, per night, is part of our “sleep is good for everybody” suite of parenting choices.