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by danielmarkbruce 1316 days ago
It's just about how are you measuring the slope? Like, when you first learn derivatives and the math teacher draws a line between two points on a curve, then draws another from points closer together, then draws the tangent, then goes through how you get to a derivative function etc.

The yoy is just using two points very far apart. The mom is using two points closer together. It would be nice but practically impossible to measure it instantaneously, mom is about as good as we get.
1 comments
fragmede 1315 days ago
I can get the prices for goods online, and then get them delivered to my house. Getting the CPI more often seems entirely feasible to me if we really wanted to.
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danielmarkbruce 1315 days ago
Maybe. But online isn't the only place to buy, and to arrive at a single number they do all kinds of adjustments to account for seasons, locations etc.

If you are right, I'd guess the cost benefit probably isn't there regardless.

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