Not in these historical U.S. records. January 24 sits near the middle of the 366-date ranking. It ranks #200 of 366 dates by total births from 1994 through 2014. Rank #1 means most common.
January 24 had 233,021 births across 21 occurrences, or 11,096 births per occurrence. That is 0.272% of the 85,712,738-birth sample, or about 1 in 368 recorded births.
It is the most common January birthday in this baseline. But 199 dates in other months have more births.
Five of its 21 occurrences fell on a Saturday or Sunday. The average across all dates is 6.0. Weekend days have fewer recorded births, so this calendar mix can raise its total. This comes from the calendar in these years, not from the date itself.
Does January 24 differ from nearby same-weekday dates?
It depends on which controls we use. In SSA 2000–2014, the primary comparison gives +0.2%. With only the 7-day controls, the result is +1.1%. With only the 14-day controls, it is -0.5%.
Because the sign changes, these results do not show clearly that January 24 has more or fewer births than nearby dates.
In the primary comparison, January 24 was above its controls in eight years and below them in seven.
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 24 with controls from the same year.
| Comparison | Years | Control observations | Difference |
|---|---|---|---|
| 7 and 14 days, holidays excluded (primary) | 15 | 57 | +0.2% |
| 7 days only | 15 | 27 | +1.1% |
| 14 days only | 15 | 30 | -0.5% |
| 7 and 14 days, no holiday exclusions | 15 | 60 | +0.5% |
How were the comparison dates chosen?
The primary controls are January 10, January 17, January 31, and February 7 in the same year. Each is 7 or 14 days from January 24, so it falls on the same weekday.
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.
By five-year period, the primary differences are +0.1% for 2000–2004, 0.0% for 2005–2009, and +0.7% 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 24 rank change over time?
Somewhat, but less than most dates. We ranked 365 recurring dates by SSA births in each five-year period. January 24 placed #188 in 2000–2004, #150 in 2005–2009, and #203 in 2010–2014. The three ranks span 53 places.
The median span for all 365 recurring dates is 159 places. This span is below that median.
Each period has one weekend occurrence, so the weekend mix does not explain the movement.
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. See also the January 2 and January 8 studies.
The methodology explains ranks and shares. Use the birthday checker to compare another date.