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+# Track B cumulative attempt ledger
+
+The Track B design (§7, "Attempt ledger") requires this record:
+
+> Maintain a cumulative attempt ledger by mechanism and gate family. Renaming a module or registration does not reset the counter. Restart after exhaustion requires new independent evidence and a new registration.
+
+**Scope.** This ledger begins with B2.
+
+**What counts as an attempt.** An attempt is either of these:
+- a scored candidate run;
+- a spent attempt under its registration's interruption and completeness rules. For B2 that means `ABORTED_AFTER_GAPS`, a second interruption, or an incomplete score file (#42 comment 6252388925, "Interruption" and step 5).
+
+A floor build that stops before any candidate run is recorded here, but is not an attempt.
+
+**When the program pauses.** Two independently justified registered successors that fail trigger `SUCCESSOR_EXHAUSTED` (design §7).
+
+## B2: the 2010→2014 earnings transport gate
+
+- **Mechanism:** candidate 3's forward-earnings law, `m6_candidate3_engine_v1`, spec SHA-256 `c9be28a28d6fcc3911723872386906af559f6d0e0d5c89a87f741a5b2c3eacd6`.
+- **Gate family:** B2's level cells.
+
+| # | Date (UTC) | Registration | Run | Outcome | Attempt? |
+|---|---|---|---|---|---|
+| — | 2026-10-15 | #42 comment 6199723681 (d1342 A: the six level cells) | Floor build only: commit `7fdc8f91`, artifact `runs/track_b_b2_floor_v1_stopped.json` (`500f801e…`) | `WEAK_POWER_OR_VACUITY` at floor build (#42 comment 6200099988) | No. No candidate ran |
+| 1 | 2026-10-18 | #42 comment 6252388925 (d1606 C1: p90 and the zero-earnings rate by cohort) | Floor commit `89c0ed9d`, score commit `430f8883`: `runs/track_b_b2_score.json` (`df82a102…`) | **`FAIL`** (#42 comment 6252752628) | **Yes, attempt 1** |
+
+**Attempt 1's failure.**
+- `earn_zero_rate.prime`'s full-support gap is 0.3034, against a tolerance of 0.202.
+- No gate seed passes.
+- Three of the four gated bounds exceed their tolerances.
+
+**Its consequence.** Under `GATE_FAIL_OR_REGRESSION_FAIL` (design §7), B2 is not admitted, and its dependants (H, B3L) cannot rely on it. Any successor needs a new registration and is counted here.