None of our calendars contain the exact number of days in one year. You can test the accuracy of any calendar or make a calendar. Here is what pressing certain keys mean in different stages of this calendar check: When entering the number of days in each month: up arrow = add one day down arrow = subtract one day space = add another month d = delete the last month entered When entering the leap years and calendar years: up arrow = add one day down arrow = subtract one day space = add another year c = copy the years currently in the list again and again until a certain year. You will be asked that year if you press this key. For example, copying 365, 365, 365, 366 would result in 365, 365, 365, 366, 365, 365, 365, 366, ...until you decide to change the pattern. d = delete the last year The number of days in every year in the cycle would be repeated over and over when checking the calendar. If you are changing speeds, there will be about two seconds of waiting after the button is pressed.
As an example, the Gregorian calendar makes the average number of days per year 365.2425. This calendar check uses 365.2422 as the number of days per year when checking a calendar. I used the backdrops in the Scratch library for pictures of seasons.
