The very basic: CY, CAY and PY

[abc123]

I have to admit I am still unclear about CY and ACY (two days before the exam ).
I don't know if I am comparing apples to apples, are the following two statements (All 10 notes) consistent with each other ?
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Ratemaking p 30
Since policy year data is not available until two calendar years after the date of the 1st policy written, the data is more mature than the prior types mentioned (CY,ACY).

WC Ratemaking, P145
Experience Period Calendar year
Advantage: It is more "mature" than similarly aged policy year or CAY experience
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[oopsieny]

the only difference between CY and ACY is in the losses. Premium is the same which is Calendar year earned premium, there is no such a thing as accident year earned premium, because it is CY EP.
AY losses is losses occurred in a given period
CY losses is losses paid during that period plus the difference in reserve during that period.

[jk]

My advice would be to draw a big "X" through Question 49 on Page 30. I'm not sure why All10 included it. It has nothing to do with the McClenahan article and seems to be based mostly on stuff that isn't on the syllabus any more. I mean, yeah, policy year data is more mature when it first becomes available, but that concept isn't addressed in the current readings.

Concentrate on Page 145, which is the current Holy Writ on PY, CY, and CAY.