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Girls' name · 1,556 recorded births

Sian

611 NZ births on record

Where Sian stands

New Zealand register · 1900–2025

611NZ births · 1971–2025

Sian has been registered 611 times in New Zealand since 1971. It did not clear the 10-birth reporting floor in 2025, so the DIA published no figure for it that year.

peak 1989 · 38BELOW THE 10-BIRTH FLOOR — NOT PUBLISHED190019632025

Its moment was 1989, when 38 babies were given it. In 6 of the years between, the name fell under the 10-birth floor and the registrar published nothing — those years are the marks along the base of the chart, not gaps in the name's use.

SOURCE·NZ Department of Internal Affairs, births by first name·CC BY 4.0. DIA lists a name only if it was given to at least 10 babies of that sex that year.·REVIEWED JUL 2026

<10NZ births in 2025 — below the reporting floor, so not published
#127its best NZ rank, in 1989
1989peak year — 38 births
858US births since 1962
611NZ births since 1971
87E&W births, 2019–2025
Saved in this browser only — no account, nothing sent anywhere.

How Sian's figures are worked out

  1. Counts come straight from the registrars: the US Social Security Administration (1880–2025) and the New Zealand Department of Internal Affairs (1900–2025). Nothing is scraped from another names site. The SSA files are the agency's own, retrieved from the Internet Archive's 2026 snapshot of ssa.gov (ssa.gov refuses automated requests); files unmodified.
  2. Ranks are computed against every name in that year's file, not just the ones this site publishes pages for — otherwise a rank would flatter every name we happen to list.
  3. The curve is drawn on births per 100,000 of that sex, not raw counts. Raw counts across eras are misleading: far more births were registered in 1957 than in 1890, so a flat count is a falling share.
  4. The reporting floor. Each registrar publishes a name only once it clears a threshold — 5 births of that sex in the US, 10 in New Zealand. Expressed as a share that threshold is itself a curve, and it is drawn on every chart here as the shaded band along the base.
  5. A missing year is a suppressed value, never a zero. Where the registrar published nothing, this site prints “below floor” or “<5”, the curve is broken rather than drawn across the gap, and the missing years are marked on the floor line. Sian was under the floor in 6 years of its NZ record.
share per 100,000 = births ÷ all births of that sex that year × 100,000
reporting floor (share) = 10 ÷ all births of that sex that year × 100,000

Full methodology →

Sian in the United States

18801900192019401960198020002020NOT PUBLISHED — BELOW THE 5-BIRTH FLOOR0.01.01.9
Births per 100,000 of that sex, so eras compare fairly. The shaded band is the 5-birth reporting floor — under it the registrar publishes nothing, so a line that stops has left the record, not fallen to zero. Sian in the United States, 1880–2025

Between 2016 and 2025 the name has been falling — down 50% as a share of girls' births.

SOURCE·US Social Security Administration, national baby-name data·Public domain. retrieved from the Internet Archive's 2026 snapshot of ssa.gov (ssa.gov refuses automated requests); files unmodified. SSA lists a name only if it was given to at least 5 babies of that sex that year.·REVIEWED JUL 2026

Sian in New Zealand

In New Zealand, Sian has been registered 611 times since 1971, peaking in 1989 with 38 births. It did not clear the DIA's 10-birth reporting floor in 2025.

1900192019401960198020002020NOT PUBLISHED — BELOW THE 10-BIRTH FLOOR0.095190
Births per 100,000 of that sex, so eras compare fairly. The shaded band is the 10-birth reporting floor — under it the registrar publishes nothing, so a line that stops has left the record, not fallen to zero. Sian in New Zealand, 1900–2025

SOURCE·NZ Department of Internal Affairs, births by first name·CC BY 4.0. DIA lists a name only if it was given to at least 10 babies of that sex that year.·REVIEWED JUL 2026

Sian in England & Wales

In England and Wales, Sian was registered 87 times between 2019 and 2025, peaking in 2020 with 20 births. It ranked #3,034 for girls in 2025 on 8 births. Across those years it has been falling.

2020NOT PUBLISHED — BELOW THE 3-BIRTH FLOOR0.03.77.5
Births per 100,000 of that sex, so eras compare fairly. The shaded band is the 3-birth reporting floor — under it the registrar publishes nothing, so a line that stops has left the record, not fallen to zero. Sian in England and Wales, 2019–2025

Seven years is a window, not a history. Unlike the American and New Zealand series this one cannot show you a name's arrival or its long decline — ONS publishes the full list only from 2019. England and Wales only: Scotland and Northern Ireland publish separately and are not counted here.

SOURCE·Office for National Statistics, baby names in England and Wales·Open Government Licence v3.0. ONS redacts any name given to 2 or fewer babies of that sex that year, under s40 of the Freedom of Information Act.·REVIEWED JUL 2026

Decade by decade in the US

US rank and births at each decade markSSA · JUL 2026
YearRankBirths
1970#6,3627
1980#6,31910
1990#6,86712
2000#6,48716
2010#14,9596
2020#7,21215

<5 = the SSA published no figure for that year. It is a suppressed value, not a zero.

Where in the United States

The states that registered Sian most often since 1962. These are lifetime totals, so they track state population as much as local taste — a name common in Wyoming will never out-count California.

StateBirths
California42
New York6
Texas5

Questions about Sian

How popular is the name Sian?

Sian did not clear the 10-birth reporting floor in 2025, so no figure was published for it that year. Its best NZ rank was #127 in 1989.

When was Sian most popular?

Sian peaked in 1989, when 38 babies in New Zealand were given the name.

Is Sian rising or falling?

Measured as a share of all girls' births, Sian has been falling between 2016 and 2025 (-50%).

Same sex, peaking within a few years of 2006, at a comparable scale. Not a taste engine — this is arithmetic on peak years, which is why it will occasionally hand you something unfashionable that is nonetheless exactly of the period.

SOURCE·US SSA (1880–2025) + NZ DIA (1900–2025) birth registrations·ranks and shares computed from the source files, see method·REVIEWED JUL 2026

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Amit Sharma

Auckland real-estate agent and marketer. Builds free, sourced data tools.