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100% refund if no snow
Well not quite if there is no snow. I spotted this at the local Home Depot today and decided to do a little research. Bottom line for me is if I was going to buy a Toro snow-blower I would register to win, but I am not about to buy one because of the “great” deal.
It might sound like a good deal, but it is more like playing the lottery. To determine my odds of winning this lottery I looked up some of the historical snowfall numbers for Washington DC. Those records should be available at the National Climate Center. But earlier this week I was over there looking for some data and found it shut down because of the ineptness of the guys we all elected to govern us. I found the numbers over at Accuweather after a Google search. They are not in a very nice form but can easily be read using R.
Depending on the source the average snowfall in DC is between 14 and 17 inches per year. So to get the 100% refund we would have to get less then about 1.5 inches this winter. It turns out that historically this has happened a total of twice in the last 120 years. Looks like I have something less than a two percent chance of winning.
I did not look at the data for other places but suspect the odds are not much better. In short this is a great deal for Toro if it gets people to buy their brand of snow-blower. I think I would do better to simply wait until late December and buy one on sale.
So if you buy one be sure to register. You might just win. The deal does not appeal to me.
Posted in Telling the Full Story
On the other hand, there’s a very interesting pattern of variance (measured over a moving 25-year window) that declines from the first measurement (1912, in the NOAA data source I found) by about half by the time you get to the mid-1950s, and then has risen to historically high levels by 2012 – driven, no doubt, by the extremes of 2009-10 and 2011-12 and 2012-13, where we came pretty darn close to the 10% threshold.
On the other other hand, I think the weather pattern may have changed in 2013 and we are in for a snowy winter. But that will just keep the variance along its increasing trend – if we get 22″ or more, or 5″ or less.