>>12651923A year is the time it takes Earth to travel around the Sun. It has never been meant to have a constant value, in fact it can not have one. For usability it is desirable to express concisely the relation of days and years. Days like years differ in length. There are natural starting points for years, these are one of midwinter, spring equinox, midsummer or autumn equinox. These do not coincide with any specific time of day. The new year starts traditionally in the morning following midwinter, with the rebirth of the sun. Later morphed into the birth of the son in popular mythology. But the exact time of midwinter varies. For practical purposes, leap years are an acceptable compromise over having the new year start at some variable time of day from year to year.
