---
title: "Price's Northampton mortality table overestimated mortality, a directional bias good for insurers and adverse to annuity buyers"
type: "claim"
status: "seedling"
audit_status: "flagged ([unverified-quant/mechanism] — a directional-bias claim with a named winner and loser rests on a Tier 3–4 secondary summary; the sourcing floor requires a Tier 1–2 primary for the mechanism and its incidence, and no independent re-fetch was possible in this headless pass; verification routed to question-verify-northampton-table-overestimated-mortality-primary)"
writer_model: "claude-opus-4-8"
source_url: "https://en.wikipedia.org/wiki/Richard_Price"
source_title: "Richard Price (Wikipedia)"
source_author: "Wikipedia contributors"
source_date: "accessed 2026-07-09; subject flourished 1723-1791"
source_quote: "good for the insurance business, and adverse for those purchasing annuities"
source_tier: 4
provenance: "Promotion from 10-inbox/raw/2026-07-09-hop-price-actuary-burke-revolution-bridge.md, 2026-07-11"
origin: "hop-batch"
derived_from: "10-inbox/raw/2026-07-09-hop-price-actuary-burke-revolution-bridge.md"
date_created: "2026-07-11T00:00:00.000Z"
tags: ["actuarial-history","insurance","mortality-tables","historical-demography","mechanism-design"]
drafted_in: ["2026-07-13-the-actuary-and-the-incendiary","the-actuary-and-the-incendiary"]
---


[[entity-richard-price|Richard Price]]'s Northampton mortality table — the survivorship data behind
[[claim-price-northampton-table-standard-actuarial-reference-century|Observations
on Reversionary Payments (1771)]] and the actuarial standard for roughly a
century — is generally described as having overestimated mortality: it implied
that people died sooner than they actually did. A table biased toward death is
"good for the insurance business, and adverse for those purchasing annuities."
The reference that anchored a century of British premium-setting therefore
carried a known directional error in the insurer's favour.

The mechanism is one of incidence. If a table overstates mortality, life-assurance
premiums computed from it are set conservatively high — the insurer collects
more than a true-longevity table would justify — while the same overstatement
makes annuities look cheaper to grant than they truly are, so an annuity
purchaser (or seller) is disadvantaged when the annuitants live longer than the
table predicted. The bias is usually attributed to defects in the underlying
Northampton parish data, such as in-migration and baptism records inflating the
apparent count of deaths relative to births.

This extends the vault's thread on demographic data that is load-bearing yet
imperfectly grounded: a mortality dataset read too straight repeats the
selection-and-censoring trap catalogued in
[[claim-osteological-paradox-skeletal-statistics-confound-past-health]], where a
sample of the dead is a distorted window on the living. It also rhymes with the
mispricing that ran through early actuarial history before age-rating —
the flat-rate annuities that
[[claim-dodson-built-age-scaled-premiums-founding-equitable-life|Dodson's
age-scaled premiums]] were built to correct.

The specific direction, magnitude, and incidence of the bias rest only on a
Tier 3–4 summary; the claim is flagged `[unverified-quant/mechanism]` and routed
to [[question-verify-northampton-table-overestimated-mortality-primary]].

**Addendum (2026-07-25).** The first empirical check on Northampton from *assured-lives* data came in about 1811, when [[entity-amicable-society-for-a-perpetual-assurance-office|the Amicable Society]]'s registrar compiled its own mortality experience and found it "more favourable than that shown by the Northampton Table" ([[claim-pensam-1811-amicable-experience-first-assured-lives-mortality-data]]). Two distinct effects point the same way and should not be collapsed: Northampton's own overestimation bias, described in this note, and the separate fact that an assured population is screened and so dies more slowly than the general population the table described.

> [!note] Seek's commentary:
> There is a quiet irony worth keeping: the table that made insurers money was
> wrong, and wrong in a way that happened to be profitable. That is a tidy story
> and therefore suspect — the "adverse for annuities" direction in particular is
> the kind of incidence claim I have seen stated backwards, so it stays flagged
> until I trace the mechanism through a primary rather than a one-line
> Wikipedia gloss. — Seek