Nielsen measurement eras: a guide
Nielsen measurement eras on the record, from the eras table.
Eras
Nielsen · Before Out-of-Home
- Span
- 1950-01-01 to 2020-09-01
- Note
- National TV measurement from Nielsen's panel alone. Out-of-Home viewing is not included; the last Super Bowl measured this way was LIV (Feb. 2, 2020).
- Basis
- Nielsen NOTES on the Super Bowl LX release.
- Source
- https://www.nielsen.com/news-center/2026/super-bowl-lx-2026/
Nielsen · Panel + Out-of-Home
- Span
- 2020-09-01 to 2025-09-01
- Note
- Nielsen began including Out-of-Home viewing in National TV measurement in September 2020. Super Bowl LV (Feb. 7, 2021) was the first Super Bowl to include OOH.
- Coverage change
- As of February 2025 Nielsen's OOH measurement covers 100% of the U.S. contiguous television population. Recorded here rather than as a fourth era: it widens the sample of an existing method, it does not change the method.
- Basis
- Nielsen NOTES on the Super Bowl LX release.
- Source
- https://www.nielsen.com/news-center/2026/super-bowl-lx-2026/
Nielsen · Big Data + Panel
- Span
- 2025-09-01 to current
- Note
- Rolled out September 2025. Super Bowl LX (Feb. 8, 2026) was the first Super Bowl reported on this methodology; all prior Super Bowls used Panel-only measurement.
- Basis
- Nielsen NOTES on the Super Bowl LX release.
- Source
- https://www.nielsen.com/news-center/2026/super-bowl-lx-2026/
Nielsen · Panel-only
- Span
- 2026-05-01 to current
- Note
- NASCAR announced May 2026 it would stop reporting BD+P and return to panel-only for the rest of 2026 (phase0b-table.md).
- Source
- https://www.sportsmediawatch.com/2026/05/nascar-ratings-change-big-data-to-panel-only/
Events on the record
- 2026-08-19
- Nielsen · Methodology change
Nielsen announced passive co-viewing measurement joining its Big Data + Panel national currency for the 2026-27 season, after a February pilot showed a 4.19 percent average lift on marquee events. paraphrase of source
From the Methodology Measurement eras
Methodologies change: households → viewers, out-of-home added (2020), Nielsen Big Data + Panel (Sept 2025), and challenger certifications (2024– ). Figures from different eras are different instruments. Era boundaries are marked on every comparison surface, and cross-era rankings are flagged rather than silently merged. See the Era Guide.
A figure also carries a measurement method, which instrument produced that number, separate from the era calendar. When Nielsen publishes both Big Data + Panel and panel-only for the same telecast, both rows stay live. That pair is not a currency disagreement and is not collapsed into a revision. When two eras overlap on a date, we leave the era unmarked rather than guess; the method label still identifies the instrument.