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FA-62916 / Insurance premium rating / Open access

Short-rate cancellation return premium: Short-rate penalty is taken on the full premium · case 01

Insured cancellations refund much less than 90% of unearned premium.

Verified by executionVariant 1 · 10 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The 10% penalty is computed on the written premium instead of on unearned premium.

VERIFIED REPAIR

Refund 90% of unearned premium.

Unsuccessful approach: Flooring the result at zero keeps the wrong penalty base.

Case contract

Input premium, term_days, days_in_force d, initiator, min_earned_permille. d<0 or term<=0 -> 'invalid'; d>=term -> 0; d==0 (flat cancel) returns the full premium. Otherwise unearned = premium*(term-d)/term; the insurer returns it in full; an insured cancellation returns 90% of unearned but never more than premium minus the minimum earned premium. Round half-up once.

Why this case matters

Premium rating engines apply ordered tabular rules where one misplaced boundary or step silently misprices policies.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
from fractions import Fraction
N = 1
observations = []
def solve(x):
    p=x['premium']; t=x['term_days']; d=x['days_in_force']
    if d<0 or t<=0: return 'invalid'
    if d>=t: return 0
    if d==0: return p
    unearned=Fraction(p*(t-d),t)
    if x['initiator']=='insured':
        ret=unearned-Fraction(p,10)
        ret=min(ret,p-Fraction(p*x['min_earned_permille'],1000))
    else:
        ret=unearned
    return math.floor(ret+Fraction(1,2))
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['insured cancels mid-term', {'premium': 167157, 'term_days': 365, 'days_in_force': 113, 'initiator': 'insured', 'min_earned_permille': 100}, 103866], ['insurer cancels mid-term', {'premium': 107827, 'term_days': 365, 'days_in_force': 285, 'initiator': 'insurer', 'min_earned_permille': 250}, 23633], ['insurer cancel early with minimum on file', {'premium': 135423, 'term_days': 365, 'days_in_force': 32, 'initiator': 'insurer', 'min_earned_permille': 400}, 123550], ['insured minimum earned binds', {'premium': 102264, 'term_days': 365, 'days_in_force': 24, 'initiator': 'insured', 'min_earned_permille': 300}, 71585], ['flat cancel by insured', {'premium': 246750, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 250}, 246750], ['flat cancel by insurer', {'premium': 77604, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 100}, 77604], ['one day in force', {'premium': 285647, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 100}, 284060], ['expiry day', {'premium': 163861, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 253298, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 250}, 'invalid'], ['six month policy insured cancel', {'premium': 169415, 'term_days': 182, 'days_in_force': 105, 'initiator': 'insured', 'min_earned_permille': 100}, 64508]], [['insured cancels mid-term', {'premium': 136580, 'term_days': 365, 'days_in_force': 120, 'initiator': 'insured', 'min_earned_permille': 100}, 82509], ['insurer cancels mid-term', {'premium': 142197, 'term_days': 365, 'days_in_force': 42, 'initiator': 'insurer', 'min_earned_permille': 100}, 125835], ['insurer cancel early with minimum on file', {'premium': 130516, 'term_days': 365, 'days_in_force': 22, 'initiator': 'insurer', 'min_earned_permille': 400}, 122649], ['insured minimum earned binds', {'premium': 155356, 'term_days': 365, 'days_in_force': 30, 'initiator': 'insured', 'min_earned_permille': 300}, 108749], ['flat cancel by insured', {'premium': 128340, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 250}, 128340], ['flat cancel by insurer', {'premium': 205493, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 250}, 205493], ['one day in force', {'premium': 125332, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 100}, 124636], ['expiry day', {'premium': 149858, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 143435, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 250}, 'invalid'], ['six month policy insured cancel', {'premium': 219606, 'term_days': 182, 'days_in_force': 115, 'initiator': 'insured', 'min_earned_permille': 100}, 72760]], [['insured cancels mid-term', {'premium': 236883, 'term_days': 365, 'days_in_force': 198, 'initiator': 'insured', 'min_earned_permille': 100}, 97544], ['insurer cancels mid-term', {'premium': 224272, 'term_days': 365, 'days_in_force': 89, 'initiator': 'insurer', 'min_earned_permille': 100}, 169586], ['insurer cancel early with minimum on file', {'premium': 271417, 'term_days': 365, 'days_in_force': 21, 'initiator': 'insurer', 'min_earned_permille': 400}, 255801], ['insured minimum earned binds', {'premium': 236806, 'term_days': 365, 'days_in_force': 27, 'initiator': 'insured', 'min_earned_permille': 300}, 165764], ['flat cancel by insured', {'premium': 50665, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 100}, 50665], ['flat cancel by insurer', {'premium': 266999, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 250}, 266999], ['one day in force', {'premium': 51282, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 250}, 50997], ['expiry day', {'premium': 202320, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 67184, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 100}, 'invalid'], ['six month policy insured cancel', {'premium': 241675, 'term_days': 182, 'days_in_force': 118, 'initiator': 'insured', 'min_earned_permille': 100}, 76486]], [['insured cancels mid-term', {'premium': 82503, 'term_days': 365, 'days_in_force': 154, 'initiator': 'insured', 'min_earned_permille': 100}, 42924], ['insurer cancels mid-term', {'premium': 137193, 'term_days': 365, 'days_in_force': 295, 'initiator': 'insurer', 'min_earned_permille': 100}, 26311], ['insurer cancel early with minimum on file', {'premium': 157674, 'term_days': 365, 'days_in_force': 15, 'initiator': 'insurer', 'min_earned_permille': 400}, 151194], ['insured minimum earned binds', {'premium': 283617, 'term_days': 365, 'days_in_force': 21, 'initiator': 'insured', 'min_earned_permille': 300}, 198532], ['flat cancel by insured', {'premium': 97666, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 100}, 97666], ['flat cancel by insurer', {'premium': 137018, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 100}, 137018], ['one day in force', {'premium': 261346, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 100}, 259894], ['expiry day', {'premium': 135749, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 260111, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 100}, 'invalid'], ['six month policy insured cancel', {'premium': 289415, 'term_days': 182, 'days_in_force': 81, 'initiator': 'insured', 'min_earned_permille': 100}, 144548]], [['insured cancels mid-term', {'premium': 59284, 'term_days': 365, 'days_in_force': 188, 'initiator': 'insured', 'min_earned_permille': 100}, 25874], ['insurer cancels mid-term', {'premium': 88844, 'term_days': 365, 'days_in_force': 105, 'initiator': 'insurer', 'min_earned_permille': 100}, 63286], ['insurer cancel early with minimum on file', {'premium': 70835, 'term_days': 365, 'days_in_force': 24, 'initiator': 'insurer', 'min_earned_permille': 400}, 66177], ['insured minimum earned binds', {'premium': 148105, 'term_days': 365, 'days_in_force': 29, 'initiator': 'insured', 'min_earned_permille': 300}, 103674], ['flat cancel by insured', {'premium': 267217, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 100}, 267217], ['flat cancel by insurer', {'premium': 201088, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 100}, 201088], ['one day in force', {'premium': 293778, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 250}, 292146], ['expiry day', {'premium': 81772, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 193452, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 100}, 'invalid'], ['six month policy insured cancel', {'premium': 273407, 'term_days': 182, 'days_in_force': 107, 'initiator': 'insured', 'min_earned_permille': 100}, 101401]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
insured cancels mid-term98691103866Failed
insurer cancels mid-term2363323633Passed
insurer cancel early with minimum on file123550123550Passed
insured minimum earned binds7158571585Passed
flat cancel by insured246750246750Passed
flat cancel by insurer7760477604Passed
one day in force284060284060Passed
expiry day00Passed
negative days rejectedinvalidinvalidPassed
six month policy insured cancel5473464508Failed

SHA-256 / ea0079a668ade9db6c70edee8b393a601e85c89bf3185aa0ec1d4a36a8151c13

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
from fractions import Fraction
N = 1
observations = []
def solve(x):
    p=x['premium']; t=x['term_days']; d=x['days_in_force']
    if d<0 or t<=0: return 'invalid'
    if d>=t: return 0
    if d==0: return p
    unearned=Fraction(p*(t-d),t)
    if x['initiator']=='insured':
        ret=max(unearned-Fraction(p,10),0)
        ret=min(ret,p-Fraction(p*x['min_earned_permille'],1000))
    else:
        ret=unearned
    return math.floor(ret+Fraction(1,2))
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['insured cancels mid-term', {'premium': 167157, 'term_days': 365, 'days_in_force': 113, 'initiator': 'insured', 'min_earned_permille': 100}, 103866], ['insurer cancels mid-term', {'premium': 107827, 'term_days': 365, 'days_in_force': 285, 'initiator': 'insurer', 'min_earned_permille': 250}, 23633], ['insurer cancel early with minimum on file', {'premium': 135423, 'term_days': 365, 'days_in_force': 32, 'initiator': 'insurer', 'min_earned_permille': 400}, 123550], ['insured minimum earned binds', {'premium': 102264, 'term_days': 365, 'days_in_force': 24, 'initiator': 'insured', 'min_earned_permille': 300}, 71585], ['flat cancel by insured', {'premium': 246750, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 250}, 246750], ['flat cancel by insurer', {'premium': 77604, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 100}, 77604], ['one day in force', {'premium': 285647, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 100}, 284060], ['expiry day', {'premium': 163861, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 253298, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 250}, 'invalid'], ['six month policy insured cancel', {'premium': 169415, 'term_days': 182, 'days_in_force': 105, 'initiator': 'insured', 'min_earned_permille': 100}, 64508]], [['insured cancels mid-term', {'premium': 136580, 'term_days': 365, 'days_in_force': 120, 'initiator': 'insured', 'min_earned_permille': 100}, 82509], ['insurer cancels mid-term', {'premium': 142197, 'term_days': 365, 'days_in_force': 42, 'initiator': 'insurer', 'min_earned_permille': 100}, 125835], ['insurer cancel early with minimum on file', {'premium': 130516, 'term_days': 365, 'days_in_force': 22, 'initiator': 'insurer', 'min_earned_permille': 400}, 122649], ['insured minimum earned binds', {'premium': 155356, 'term_days': 365, 'days_in_force': 30, 'initiator': 'insured', 'min_earned_permille': 300}, 108749], ['flat cancel by insured', {'premium': 128340, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 250}, 128340], ['flat cancel by insurer', {'premium': 205493, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 250}, 205493], ['one day in force', {'premium': 125332, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 100}, 124636], ['expiry day', {'premium': 149858, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 143435, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 250}, 'invalid'], ['six month policy insured cancel', {'premium': 219606, 'term_days': 182, 'days_in_force': 115, 'initiator': 'insured', 'min_earned_permille': 100}, 72760]], [['insured cancels mid-term', {'premium': 236883, 'term_days': 365, 'days_in_force': 198, 'initiator': 'insured', 'min_earned_permille': 100}, 97544], ['insurer cancels mid-term', {'premium': 224272, 'term_days': 365, 'days_in_force': 89, 'initiator': 'insurer', 'min_earned_permille': 100}, 169586], ['insurer cancel early with minimum on file', {'premium': 271417, 'term_days': 365, 'days_in_force': 21, 'initiator': 'insurer', 'min_earned_permille': 400}, 255801], ['insured minimum earned binds', {'premium': 236806, 'term_days': 365, 'days_in_force': 27, 'initiator': 'insured', 'min_earned_permille': 300}, 165764], ['flat cancel by insured', {'premium': 50665, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 100}, 50665], ['flat cancel by insurer', {'premium': 266999, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 250}, 266999], ['one day in force', {'premium': 51282, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 250}, 50997], ['expiry day', {'premium': 202320, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 67184, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 100}, 'invalid'], ['six month policy insured cancel', {'premium': 241675, 'term_days': 182, 'days_in_force': 118, 'initiator': 'insured', 'min_earned_permille': 100}, 76486]], [['insured cancels mid-term', {'premium': 82503, 'term_days': 365, 'days_in_force': 154, 'initiator': 'insured', 'min_earned_permille': 100}, 42924], ['insurer cancels mid-term', {'premium': 137193, 'term_days': 365, 'days_in_force': 295, 'initiator': 'insurer', 'min_earned_permille': 100}, 26311], ['insurer cancel early with minimum on file', {'premium': 157674, 'term_days': 365, 'days_in_force': 15, 'initiator': 'insurer', 'min_earned_permille': 400}, 151194], ['insured minimum earned binds', {'premium': 283617, 'term_days': 365, 'days_in_force': 21, 'initiator': 'insured', 'min_earned_permille': 300}, 198532], ['flat cancel by insured', {'premium': 97666, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 100}, 97666], ['flat cancel by insurer', {'premium': 137018, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 100}, 137018], ['one day in force', {'premium': 261346, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 100}, 259894], ['expiry day', {'premium': 135749, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 260111, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 100}, 'invalid'], ['six month policy insured cancel', {'premium': 289415, 'term_days': 182, 'days_in_force': 81, 'initiator': 'insured', 'min_earned_permille': 100}, 144548]], [['insured cancels mid-term', {'premium': 59284, 'term_days': 365, 'days_in_force': 188, 'initiator': 'insured', 'min_earned_permille': 100}, 25874], ['insurer cancels mid-term', {'premium': 88844, 'term_days': 365, 'days_in_force': 105, 'initiator': 'insurer', 'min_earned_permille': 100}, 63286], ['insurer cancel early with minimum on file', {'premium': 70835, 'term_days': 365, 'days_in_force': 24, 'initiator': 'insurer', 'min_earned_permille': 400}, 66177], ['insured minimum earned binds', {'premium': 148105, 'term_days': 365, 'days_in_force': 29, 'initiator': 'insured', 'min_earned_permille': 300}, 103674], ['flat cancel by insured', {'premium': 267217, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 100}, 267217], ['flat cancel by insurer', {'premium': 201088, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 100}, 201088], ['one day in force', {'premium': 293778, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 250}, 292146], ['expiry day', {'premium': 81772, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 193452, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 100}, 'invalid'], ['six month policy insured cancel', {'premium': 273407, 'term_days': 182, 'days_in_force': 107, 'initiator': 'insured', 'min_earned_permille': 100}, 101401]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
insured cancels mid-term98691103866Failed
insurer cancels mid-term2363323633Passed
insurer cancel early with minimum on file123550123550Passed
insured minimum earned binds7158571585Passed
flat cancel by insured246750246750Passed
flat cancel by insurer7760477604Passed
one day in force284060284060Passed
expiry day00Passed
negative days rejectedinvalidinvalidPassed
six month policy insured cancel5473464508Failed

SHA-256 / c2ca46ec452a195b7abc5757024028e2a58df53777e59683a4b44f1e393afdac

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import math
from fractions import Fraction
N = 1
observations = []
def solve(x):
    p=x['premium']; t=x['term_days']; d=x['days_in_force']
    if d<0 or t<=0: return 'invalid'
    if d>=t: return 0
    if d==0: return p
    unearned=Fraction(p*(t-d),t)
    if x['initiator']=='insured':
        ret=unearned*Fraction(90,100)
        ret=min(ret,p-Fraction(p*x['min_earned_permille'],1000))
    else:
        ret=unearned
    return math.floor(ret+Fraction(1,2))
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['insured cancels mid-term', {'premium': 167157, 'term_days': 365, 'days_in_force': 113, 'initiator': 'insured', 'min_earned_permille': 100}, 103866], ['insurer cancels mid-term', {'premium': 107827, 'term_days': 365, 'days_in_force': 285, 'initiator': 'insurer', 'min_earned_permille': 250}, 23633], ['insurer cancel early with minimum on file', {'premium': 135423, 'term_days': 365, 'days_in_force': 32, 'initiator': 'insurer', 'min_earned_permille': 400}, 123550], ['insured minimum earned binds', {'premium': 102264, 'term_days': 365, 'days_in_force': 24, 'initiator': 'insured', 'min_earned_permille': 300}, 71585], ['flat cancel by insured', {'premium': 246750, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 250}, 246750], ['flat cancel by insurer', {'premium': 77604, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 100}, 77604], ['one day in force', {'premium': 285647, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 100}, 284060], ['expiry day', {'premium': 163861, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 253298, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 250}, 'invalid'], ['six month policy insured cancel', {'premium': 169415, 'term_days': 182, 'days_in_force': 105, 'initiator': 'insured', 'min_earned_permille': 100}, 64508]], [['insured cancels mid-term', {'premium': 136580, 'term_days': 365, 'days_in_force': 120, 'initiator': 'insured', 'min_earned_permille': 100}, 82509], ['insurer cancels mid-term', {'premium': 142197, 'term_days': 365, 'days_in_force': 42, 'initiator': 'insurer', 'min_earned_permille': 100}, 125835], ['insurer cancel early with minimum on file', {'premium': 130516, 'term_days': 365, 'days_in_force': 22, 'initiator': 'insurer', 'min_earned_permille': 400}, 122649], ['insured minimum earned binds', {'premium': 155356, 'term_days': 365, 'days_in_force': 30, 'initiator': 'insured', 'min_earned_permille': 300}, 108749], ['flat cancel by insured', {'premium': 128340, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 250}, 128340], ['flat cancel by insurer', {'premium': 205493, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 250}, 205493], ['one day in force', {'premium': 125332, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 100}, 124636], ['expiry day', {'premium': 149858, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 143435, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 250}, 'invalid'], ['six month policy insured cancel', {'premium': 219606, 'term_days': 182, 'days_in_force': 115, 'initiator': 'insured', 'min_earned_permille': 100}, 72760]], [['insured cancels mid-term', {'premium': 236883, 'term_days': 365, 'days_in_force': 198, 'initiator': 'insured', 'min_earned_permille': 100}, 97544], ['insurer cancels mid-term', {'premium': 224272, 'term_days': 365, 'days_in_force': 89, 'initiator': 'insurer', 'min_earned_permille': 100}, 169586], ['insurer cancel early with minimum on file', {'premium': 271417, 'term_days': 365, 'days_in_force': 21, 'initiator': 'insurer', 'min_earned_permille': 400}, 255801], ['insured minimum earned binds', {'premium': 236806, 'term_days': 365, 'days_in_force': 27, 'initiator': 'insured', 'min_earned_permille': 300}, 165764], ['flat cancel by insured', {'premium': 50665, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 100}, 50665], ['flat cancel by insurer', {'premium': 266999, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 250}, 266999], ['one day in force', {'premium': 51282, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 250}, 50997], ['expiry day', {'premium': 202320, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 67184, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 100}, 'invalid'], ['six month policy insured cancel', {'premium': 241675, 'term_days': 182, 'days_in_force': 118, 'initiator': 'insured', 'min_earned_permille': 100}, 76486]], [['insured cancels mid-term', {'premium': 82503, 'term_days': 365, 'days_in_force': 154, 'initiator': 'insured', 'min_earned_permille': 100}, 42924], ['insurer cancels mid-term', {'premium': 137193, 'term_days': 365, 'days_in_force': 295, 'initiator': 'insurer', 'min_earned_permille': 100}, 26311], ['insurer cancel early with minimum on file', {'premium': 157674, 'term_days': 365, 'days_in_force': 15, 'initiator': 'insurer', 'min_earned_permille': 400}, 151194], ['insured minimum earned binds', {'premium': 283617, 'term_days': 365, 'days_in_force': 21, 'initiator': 'insured', 'min_earned_permille': 300}, 198532], ['flat cancel by insured', {'premium': 97666, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 100}, 97666], ['flat cancel by insurer', {'premium': 137018, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 100}, 137018], ['one day in force', {'premium': 261346, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 100}, 259894], ['expiry day', {'premium': 135749, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 260111, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 100}, 'invalid'], ['six month policy insured cancel', {'premium': 289415, 'term_days': 182, 'days_in_force': 81, 'initiator': 'insured', 'min_earned_permille': 100}, 144548]], [['insured cancels mid-term', {'premium': 59284, 'term_days': 365, 'days_in_force': 188, 'initiator': 'insured', 'min_earned_permille': 100}, 25874], ['insurer cancels mid-term', {'premium': 88844, 'term_days': 365, 'days_in_force': 105, 'initiator': 'insurer', 'min_earned_permille': 100}, 63286], ['insurer cancel early with minimum on file', {'premium': 70835, 'term_days': 365, 'days_in_force': 24, 'initiator': 'insurer', 'min_earned_permille': 400}, 66177], ['insured minimum earned binds', {'premium': 148105, 'term_days': 365, 'days_in_force': 29, 'initiator': 'insured', 'min_earned_permille': 300}, 103674], ['flat cancel by insured', {'premium': 267217, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insured', 'min_earned_permille': 100}, 267217], ['flat cancel by insurer', {'premium': 201088, 'term_days': 365, 'days_in_force': 0, 'initiator': 'insurer', 'min_earned_permille': 100}, 201088], ['one day in force', {'premium': 293778, 'term_days': 180, 'days_in_force': 1, 'initiator': 'insurer', 'min_earned_permille': 250}, 292146], ['expiry day', {'premium': 81772, 'term_days': 365, 'days_in_force': 365, 'initiator': 'insured', 'min_earned_permille': 100}, 0], ['negative days rejected', {'premium': 193452, 'term_days': 365, 'days_in_force': -1, 'initiator': 'insured', 'min_earned_permille': 100}, 'invalid'], ['six month policy insured cancel', {'premium': 273407, 'term_days': 182, 'days_in_force': 107, 'initiator': 'insured', 'min_earned_permille': 100}, 101401]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
insured cancels mid-term103866103866Passed
insurer cancels mid-term2363323633Passed
insurer cancel early with minimum on file123550123550Passed
insured minimum earned binds7158571585Passed
flat cancel by insured246750246750Passed
flat cancel by insurer7760477604Passed
one day in force284060284060Passed
expiry day00Passed
negative days rejectedinvalidinvalidPassed
six month policy insured cancel6450864508Passed

SHA-256 / 8c6d8f7d5b6d5cb471c05c630920bceb4897fca789049505fe23d6fafbd9ece3

Verification & scope

A deterministic bounded teaching model of a stipulated toy rating contract. Amounts are integer cents and factors exact rationals; it makes no claim of conformance with any filed rating plan, bureau manual or jurisdiction. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:47:09.419424+00:00.

Case digest / 14bf6d076ec7923bde62c7afaf0f0f1a9c23fde9e95ce3cbe6c2fc42af8117c8