Not in these historical U.S. records. March 5 is less common than most dates, but it is not among the rarest. It ranks #228 of 366 dates by total births from 1994 through 2014. Rank #1 means most common.
March 5 had 231,388 births across 21 occurrences, or 11,018 births per occurrence. That is 0.270% of the 85,712,738-birth sample, or about 1 in 370 recorded births.
Within March, March 5 ranks #12 of 31 dates.
Does March 5 differ from nearby same-weekday dates?
Not clearly. In SSA 2000–2014, the primary comparison gives 0.0%. The three comparisons with holiday exclusions all stay within 1% of the controls.
When weekdays match, March 5 looks much like the dates around it.
In the primary comparison, March 5 was above its controls in six years and below them in nine.
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 March 5 with controls from the same year.
| Comparison | Years | Control observations | Difference |
|---|---|---|---|
| 7 and 14 days, holidays excluded (primary) | 15 | 57 | 0.0% |
| 7 days only | 15 | 30 | 0.0% |
| 14 days only | 15 | 27 | 0.0% |
| 7 and 14 days, no holiday exclusions | 15 | 60 | +0.3% |
How were the comparison dates chosen?
The primary controls are February 19, February 26, March 12, and March 19 in the same year. In leap years, the February controls are February 20 and February 27. Each is 7 or 14 days from March 5, so it falls on the same weekday.
In some years, a planned control falls on Washington’s Birthday. 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 -0.3% for 2000–2004, 0.0% for 2005–2009, and +0.3% 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 March 5 rank change over time?
Yes. We ranked 365 recurring dates by SSA births in each five-year period. March 5 placed #200 in 2000–2004, #315 in 2005–2009, and #150 in 2010–2014. The three ranks span 165 places.
The median span for all 365 recurring dates is 159 places. This span is close to that median.
Each period has only five occurrences of March 5. It fell on a weekend twice in 2005–2009 and once in each other period. The period with more weekend occurrences has the less common rank.
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 March guide for the full month ranking. Compare the nearby March 17 study.
The methodology explains ranks and shares. Use the birthday checker to compare another date.