The Hermetic Lunar Week Calendar (HLWC) is a proposal for calendar reform by Peter Meyer. It is a lunisolar calendar which uses the lunar week (a quarter of a lunation). Each week has normally 7 days, sometimes 8, occasionally 6 and rarely 9 (average 7.382647 days). HLWC time is 6 hours behind of conventional time. Each week begins on the HLWC day after the dark moon (new moon), half moon (waxing), full moon or half moon (waning). Each month starts on the HLWC day after the dark moon (new moon) and each year starts on the HLWC day after the closest dark moon (new moon) to the vernal equinox. Each month has 29 or 30 days. Each year has 12 or 13 months. The names of the months are: