(CNN) -- Here's a look at what you need to know about Mother's Day, which is always celebrated on the second Sunday in May. In 2014, the holiday will be celebrated on May 11th.
Facts: There were an estimated 85.4 million mothers in the U.S. in 2009.
Initially, people observed Mother's Day by attending church and writing letters to their mothers. Eventually, sending cards and giving presents and flowers became part of the tradition.
141 million Mother's Day cards are exchanged annually in the United States.
Consumers purchase an average of 2.8 Mother's Day cards.
Approximately 65% of card sales occur five days prior to Mother's Day.
More people purchase fresh flowers and plants for Mother's Day than for any other holiday except Christmas/Hanukkah. Mother's Day accounts for one-fourth of all holiday sales of flowers and plants.
In 2013, the National Retail Federation estimated that U.S. consumers would spend more than $20 billion celebrating Mother's Day.
According to the Insure.com 2013 Mother's Day Index, various tasks Moms perform at home would be worth $59,862 (down from $60,182 in 2012) a year in the professional world.
Anna Jarvis started the tradition of wearing a carnation on Mother's Day. A colored carnation means that a person's mother is living. A white carnation indicates that a person's mother is dead.
History: 1872 - Julia Ward Howe, who is a pacifist, suffragette, and writer of the "Battle Hymn of the Republic," first suggests Mother's Day in the United States. She suggests the day as a day mothers could rally for peace and for several years, she holds an annual Mother's Day meeting in Boston.
1908 - Anna Jarvis begins a campaign for a nationwide observance of Mother's Day in honor of her late mother, a community health advocate. Anna Jarvis was deeply dismayed over the commercialization of Mother's Day. Before she died in 1948, she admitted that she regretted ever starting the holiday.
May 9, 1914 - President Woodrow Wilson signs a bill recognizing Mother's Day as a national holiday.