Superseded, 27 September 2026. This page is the record of Call #4 (6 Aug) as presented, and keeps the figures and vocabulary of that date. In paper v5.2 (27 September 2026): the seven-policyholder cohort earns +$5,306.98 (was +$3,127); mean CLV rises 4.3× across tenure (was 4.1×); filing / planning basis are now the revenue-neutral / level-effect basis. The current state is on the project hub.
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You asked whether loss depends on tenure. It does — here is what to do about it

CAS Ratemaking Working Group  ·  Bi-Weekly Call #4  ·  Phase 4 close-out + tranche-2 first-draft bundle
Thu Aug 6, 2026 · 4:30 PM ET
30 min · hard stop 5:00 PM
Researcher: Pramod Misra (5G Vector)
POG: Mondello · Robinson · Paik · Werner · Kozlowski
Four decisions, all downstream of Mark's question on July 16. We measured the tenure gradient, built it into all six models, and found something that inverts the obvious conclusion — so these are genuine choices, not ratifications. The green banner shows what you asked → what we built; then pick what we carry into the paper and the toolkit. Q1 and Q3 are the ones that matter most; if we run out of time, answer those by email and we will proceed on the recommendations for the rest. ★ = researcher's recommendation.
Q1 Tenure-varying loss — what becomes the default?M. MONDELLO

Which basis should the published headline use?

A
Keep flat as the headline; publish the tenure gradient as a sensitivity dimension until the NAIC cross-carrier test confirms it★ rec
B
Make the filing basis (revenue-neutral relativity) the headline now
C
Make the planning basis (level effect, +$2.62M on the book) the headline now
D
Publish flat and tenure side-by-side everywhere, as we do for the two CLV variants
Q2 Where should the curve come from?

What should the published default curve be, given users will apply this to their own books?

A
Fit on the user's own book, with ours as a documented illustration only★ rec
B
Ship our fitted curve as a general-purpose default
C
Credibility-blend the user's own experience toward an industry curve
D
Judgmentally selected curve, actuary-supplied, no default at all
Q3 May a tenure relativity enter a filed exhibit?
Heads-up: “loss ratio improves with tenure” and “give loyal policyholders a discount” are not the same proposition. A tenure relativity built naively from a loss-ratio-by-tenure exhibit is likely backwards.

How should the paper position tenure in rate indications?

A
Planning use only. Publish the filing-basis result as a cautionary finding, recommend against a tenure relativity without further work★ rec
B
Permit it in filings on the unconstrained variant, with the four-fifths screen extended to age bands
C
Silent — out of scope for this paper; present the mechanics without a recommendation
D
Escalate to a dedicated section with a state-by-state review (CA / NY / CO)
Q4 Case studies — which grain goes in the paper?M. MONDELLO

What carries into the paper's exposition?

A
Lead with the 7-policyholder cohort, then scale to tenure bands and the full book★ rec
B
Tenure bands only — the 4.1× CLV gradient is the cleaner headline
C
CLV quintiles only — matches the ratemaking relativity exhibits
D
All of it as an appendix; keep the main text purely narrative
Reserve question — for Call #5 (Aug 13), flagging it now so you can think about it. Everything above rests on a gradient measured on one synthetic book. The NAIC five-year cross-carrier reproducibility test is what decides whether the 4.22%/year credit is a general phenomenon or an artifact of our generator — and it is not yet run. We need your view on the protocol: which lines (personal auto / homeowners / both), how many carriers constitutes a fair test, and what dispersion in the fitted credit you would accept before calling it reproducible. If it fails, Q1 and Q2 collapse to “user-supplied curve only” and we will say so plainly in the paper.
This research project has been funded by the Casualty Actuarial Society.