[quote]Bill Roberts wrote:
You still wound up choosing a peak that, last time around, didn’t sustain itself at all.
[/quote]
If you consider only 1950-2000, yes it appears the trendline would be pretty flat. However, just like what you say about the peaks, over the last 30 years, neither of the two valleys could sustain themselves either, and these low points (1984, 1997) would appear to fall directly on the trendline. This would lead me to believe that if we only want to consider these 50 years, then we do not have a linear trend. (Checking the chart really quick)
I guess I would be wrong, the line does definitely trend up, and gives a formula y=.1488x-181.79, which gives a value of 117.30 for 2010, still no where near the 40% suggested, but lower than I would suggest. However, this trend required throwing out all of the most recent data and ignores all appreciation that happened during the last decade that was indeed sustainable, ie, most of what happened between the coastal states, and does assume a linear trend.
Actually, the more of history I cut out and the more relevance I put on just the last 30 years supports my argument even more, I do agree that prices 100 years ago have little relevance to todays. So let’s look again at the trend for just the last 30 years. y=2.0236x-3907.6 gives (2010, 159.84)
[quote]
I don’t care whether you go back only as far as say 1960, or you go to 1950, or you go to 1965, or what have you.
I’d suggest re-running your analysis so as to not go back so extremely far, and try running it both with obvious bubbles and obvious short-term crashes removed, as we are not interested in predicting bubble or crash prices, but prices that might be considered long-term typical.
If you do this, I’m pretty sure your trendline will be quite different than you’re calculating now, and present prices will be substantially above it.[/quote]
The problem with doing this is that housing prices have not shown an obvious trend since 1975. Disregarding the bubbles and crashes disregards government programs that were behind these occurences that are still in place today.
This is why I displayed the second graph (the ratio of prices to costs), to give a better baseline of the value of the building and factor out location and as much other appreciation as possible. If we start with the actual cost to build and just look at what the markup is over that, we see a graph with no distinct trend, but it also shows a markup well below most historical values.