> The periods aren't "cherry-picked." If you'd actually look at the plotted effective capital gains rate, you'd see a clear difference in tax policy in those three periods.
The first period includes within it a perfectly flat period longer than shortest of the periods you chose followed by a period of equal length that is more consistently increasing than the (mostly flat) period you've held up as an increasing trend, and then a period nearly as long as your shortest that is as consistently and more sharply decreasing than the one you hold up as showing a decreasing trend.
So, no, I don't see natural breakpoints in the data.
(You've kind of muddied whether you are more concerned with the actual cap gains tax rate or the trend in changes to the rate, seeming to lean a little more heavily on the former, so I focussed on that in my criticism; but if you care about the rates instead of the deltas the periods you chose still make no sense, for similar reasons.)
> The first period includes within it a perfectly flat period longer than shortest of the periods you chose followed by a period of equal length that is more consistently increasing than the (mostly flat) period you've held up as an increasing trend, and then a period nearly as long as your shortest that is as consistently and more sharply decreasing than the one you hold up as showing a decreasing trend.
It sounds like you're referring to the "maximum tax rate on long term gains." As I stated, I used the "effective capital gains tax rate," which is the average rate that is being taxed (long term cap gains tax is different than short term).
The first period includes within it a perfectly flat period longer than shortest of the periods you chose followed by a period of equal length that is more consistently increasing than the (mostly flat) period you've held up as an increasing trend, and then a period nearly as long as your shortest that is as consistently and more sharply decreasing than the one you hold up as showing a decreasing trend.
So, no, I don't see natural breakpoints in the data.
(You've kind of muddied whether you are more concerned with the actual cap gains tax rate or the trend in changes to the rate, seeming to lean a little more heavily on the former, so I focussed on that in my criticism; but if you care about the rates instead of the deltas the periods you chose still make no sense, for similar reasons.)