It looks like the Iranian calendar would have each year of a different length, since
The Iranian New Year begins at the midnight nearest to the instant of the northern spring equinox, as determined by astronomic calculations for the meridian (52.5°E)
This would make this kind of calendar extremely complicated to handle especially when not using computers
It looks like the Iranian calendar would have each year of a different length, since
This would make this kind of calendar extremely complicated to handle especially when not using computers