One hundred and fifty years of federal census data and one thing is clear: the growing trend of working mothers in the United States is as old as Lincoln's presidency. We recently examined 150 years of U.S. Federal Census records to understand the role of mothers in the workforce and found the national average has grown 800% over the past century and a half ? from 7.5% working mothers in 1860 to 67% today. Mom's plates have been full for generations, but it wasn't until the US Census Bureau started recording occupation data for women in 1860 that we really begin to see and understand their role in the nation's workforce, said Todd Godfrey, Global Content Acquisition at Ancestry.com. Exploring the histories of the women in your family tree can help you better understand the times in which they lived and find commonalities among working mothers that transcend time. Growth Over the Decades According to the analysis, every decade since 1860 shows a different rate of growth, influenced by what was happening in the nation at the time. The woman's suffrage movement, regional trends and wartime all contributed to growth rates after the turn of the century. With so many fathers going off to war in the first half of 1940, the nation called upon women to join the workforce like never before. This ushered in the highest growth rates for working women in the country since 1860, with double-digit growth continuing for the next four decades (1950-1990). The highest growth over the entire 150-year timeframe occurred in 1980 (12.6%), boosting the percentage of working mothers to 52%. [widgets_on_pages id="working-mothers-1"] South Dakota Boasts Largest Growth and Percentage of Working Moms Most interesting in the Ancestry.com analysis were the 10 states that showed the most working mothers, compared to the 10 states with the fewest. In analyzing the numbers, it was apparent that states seemed to group together on rate of growth, Godfrey said. For nearly 80 years the highest percentage of working mothers was in the South and the lowest percentage was in the Midwest. In the most recent four decades the Southern states traded places with the Midwest states which now make up the majority of the top 10 states. Eight states dominated the bottom of the working mothers list for much of the 20th century: South Dakota, North Dakota, Iowa, Minnesota, Nebraska, Wisconsin, Vermont, and Kansas. However these states would climb to the top of the list by 2000 taking eight of the top ten spots with the largest percentages of working mothers for the past three decades. Among the eight, South Dakota has had the highest growth and boasts the highest percentage of working mothers as of the last census in 2010 (79.9%). As of 2010, the top 10 states with working mothers include:  

• South Dakota: 79.9%
• North Dakota: 78.9%
• Iowa: 78.4%
• Minnesota: 78.0%
• Nebraska: 77.4%
• Wisconsin: 76.6%
• Vermont: 75.4%
• New Hampshire: 73.5%
• Kansas: 73.3%
• Maine: 71.1%

[widgets_on_pages id="working-mothers-2"] Working moms have played an integral role in helping shape the American workforce over the past 150 years. From homestead settler in the mid-1800s to today's entrepreneurs and executives, one thing is certain ? there's no slowing the nation's working mothers! Methodology: Data analysis is based on data from the Integrated Public Use Microdata Series (IPUMS) which has a random sample of household data taken from each decennial census of the U.S. Federal Census. Mothers were defined as women living with at least one child in the household. Labor force participation was determined based on occupation for 1850-1930 and modern labor force participation definition for 1940 onwards. States or territories with less than 70 mothers in the sample for a given year were dropped from the analysis for that year.