International Fixed Calendar
The International Fixed Calendar simplifies dates and accounting because every month has the same number of days and dates and days of the week are fixed. The same calendar can be used every year! The main difference is the extra month of Sol in the middle and the “intercalary days” (Year Day and Leap Day) that are outside the week days.
Wikipeadia explains the pros and cons well of it and calendar reform proposals in general. Kodak company is famous for having used it for 60 years.
I got tired of having to check the Gregorian calendar every fortnight to keep up with the date of housemate spreadsheets. Keeping this link handy in your phone and computer makes things easy. I adapted the old image (below) to incorporate the Gregorian calendar (above) for easy reference on paper. The watermark shows the Gregorian months (not dates). You’ll notice the months lag behind the IFC in the first half of the year and in the second half they precede because of the extra month in the middle, Sol. The end of the financial year (which in Australia is the 30th of June in the Gregorian calendar) falls on the 13th of Sol in the IFC, because the Gregorian calendar has 181 days in the first half of the year and 184 in the second half. If we used the IFC, the end of the financial year would be the 14th of Sol, exactly in the middle. Quarterly periods in the IFC are exactly 13 weeks; January 1st – April 7, April 8 – Sol 14, Sol 15 – Sept 21, Sept 22 – Dec 28. 
“Year Day” could be an accounting-free day, where everything is done for free, as envisaged by The Free World Charter.
8 November, 2017 update:
Email to The World Calendar website
Hello.
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