When the 16th Amendment, which allowed Congress to institute income tax, was adopted on February 3, 1913, Congress actually chose March 1st. as the deadline for filing returns. However, when the Revenue Act of 1918 was passed, the date was changed to March 15, without any real known reason.
The next big overhaul came in 1955 when, in addition to many tax-code revisions, the date for when taxes were due changed again, to April 15. According to many sources, the explanation for this change was because at that time the government had to pay more refunds, so it wanted more time to hold on to the money. While some may think this change was to assist the government, the law is still in the Americans’ favor. By law, the government must mail your refund within 45 days or they have to pay interest.
Sandi Duncan is the Managing Editor of the Farmers' Almanac. 
If you notice a hole in the upper left-hand corner of your Farmers' Almanac, don't return it to the store! That hole isn't a defect; it's a part of history. Starting with the first edition of the Farmers' Almanac in 1818, readers used to nail holes into the corners to hang it up in their homes, barns, and outhouses (to provide both reading material and toilet paper). In 1910, the Almanac's publishers began pre-drilling holes in the corners to make it even easier for readers to keep all of that invaluable information (and paper) handy.
