365-day calendar 365-day calendar A 365-day calendar consists of exactly 365 days per year (no leap days), and is primarily used in computer models and as an assumption in every-day calculations. For example, a calculation of a daily rate may use an annual total divided by exactly 365. Interest rates in some banks are calculated using a 365-day calendar. Some Mesoamerican calendars used a 365-day year with no leap year, resulting in a gradual shift of the seasons relative to the calendar. This includes the Maya Haab' and the Aztec Xiuhpohualli calendars. Some versions of the Zoroastrian calendar also use a fixed
Mesoamerican writing systems skin covered with stucco. These codices are read in boustrophedon, a zigzag style in which the reader follows red lines that indicate the way to read. Most of the current knowledge about the writing of the Mixtecans is due to the work of Alfonso Caso, who undertook the task of deciphering the code based on a set of pre-Columbian and colonial documents of the Mixtec culture. Although the Mixtecs had a set of symbols that allowed them to record historical dates, they did not use the long count calendar characteristic of other southeast Mesoamerican writing systems. Instead, the codices that