Not especially. January 6 is less common than most dates in these historical U.S. records, but it is not among the rarest. It ranks #268 of 366 dates by total births from 1994 through 2014. Rank #1 means most common.
January 6 had 229,776 births across 21 occurrences, or 10,942 births per occurrence. That is 0.268% of the 85,712,738-birth sample, or about 1 in 373 recorded births.
It ranks #11 of the 31 January dates.
Does January 6 differ from nearby same-weekday dates?
January 6 has slightly more births than its controls in every planned comparison. In SSA 2000–2014, the primary comparison gives +1.8%. The planned comparisons range from +0.8% to +3.1%.
The 14-day comparison differs by less than 1%, so we treat the result as weak.
In the primary comparison, January 6 was above its controls in fourteen years and below them in one.
Baseline ranks use historical U.S. CDC/NCHS and SSA records, 1994–2014. The percentage differences use SSA 2000–2014 alone. Each table row compares January 6 with controls from the same year.
| Comparison | Years | Control observations | Difference |
|---|---|---|---|
| 7 and 14 days, holidays excluded (primary) | 15 | 28 | +1.8% |
| 7 days only | 15 | 15 | +3.1% |
| 14 days only | 13 | 13 | +0.8% |
| 7 and 14 days, no holiday exclusions | 15 | 30 | +2.1% |
How were the comparison dates chosen?
The planned controls are December 23, December 30, January 13, and January 20. Each is 7 or 14 days from January 6, so it falls on the same weekday. The December dates fall in the previous year. The design uses only same-year controls, so it omits them. Every comparison uses only January 13 and January 20.
In some years, a planned control falls on Martin Luther King Jr. Day. We remove that control under the standard observed federal holiday rules. The year keeps its other controls.
The 14-day comparison uses 13 years. In 2003 and 2014, every 14-day control was excluded or fell outside the year.
By five-year period, the primary differences are +2.0% for 2000–2004, +2.8% for 2005–2009, and +0.6% for 2010–2014.
To combine the years, we divide the summed target births by the summed annual control means. Then we subtract one and multiply by 100. The result is not an average of annual percentages.
Does the January 6 rank change over time?
Yes. We ranked 365 recurring dates by SSA births in each five-year period. January 6 placed #311 in 2000–2004, #295 in 2005–2009, and #175 in 2010–2014. The three ranks span 136 places.
The median span for all 365 recurring dates is 159 places. This span is below that median.
Each period has only five occurrences of January 6. It fell on a weekend twice in 2000–2004, twice in 2005–2009, and once in 2010–2014. The periods with more weekend occurrences have less common ranks.
These ranks use raw birth counts. The ranking-stability study also compares annual shares and weekday-relative scores for every date.
Sources and limits
Baseline totals and ranks use FiveThirtyEight’s pinned U.S. birth files. We use CDC/NCHS for 1994–1999 and SSA for 2000–2014, so no year comes from both sources. Annual comparisons use SSA alone.
The source series have different administrative coverage. These records do not describe worldwide births, everyone alive today, or current birth rates.
The daily totals do not record delivery methods or scheduling decisions. Weekday matching does not remove every seasonal difference. Federal holiday rules identify calendar dates, not hospital schedules.
Use the January guide for the full month ranking. Compare the nearby January 2 and January 8 studies.
The methodology explains ranks and shares. Use the birthday checker to compare another date.