It wasn’t just the women’s lib movement that put mothers into the workplace. The trend is at least as old as Lincoln’s presidency, when 7.5 percent of mothers worked.

Today, 67 percent of mothers with children at home work, according to, which examined 150 years of census records to determine the trends of working moms.

But it wasn’t always a steady climb. Some years, that number dropped. Others, like in wartime, it jumped. The largest increase was in 1980, when working moms pushed past the halfway mark (52 percent), and increased by 12.6 percent over the year prior.

Just think of your own family history: My grandmother was a telephone operator after her spouse got sick. My own mother stopped working as a teacher until my brother and I were older.

What’s also interesting is the percentage of working mothers per state. South Dakota has the highest percentage in 2010 at 79.9 percent. Meanwhile, New York isn’t even in the top 10 now — or anytime in the last 150 years. Take a look.