Mewa calculation

Every 'Lunar' day is associated with a Mewa. A problem calculating the right Mewa is that sometimes 'Lunar' days are omitted and sometimes 'Lunar' days are doubled. This depends on the solar day which begins at 05:00 and when the 'Lunar' begins. Normally the 'Lunar' day count start at new moon and the next 'Lunar' day start after the moon moved 12º.
A general rule for 'Lunar' days is:
- A lunar day is omitted when the 'Lunar' day starts after 05:00 ( start of solar day ) and ends before the beginning of the next solar day ( the next lunar day starts on the same solar day ).
- A lunar day is doubled when it starts before a solar day and ends on the solar day after that solar day.

Mewas change in the sequence White 1, Black 2, Blue 3, Green 4, Yellow 5, White 6, Red 7, White 8 and Red 9.

When there is an omitted lunar day the Mewa changes also on this day.
When there is a double day the Mewa stays the same.

Month Dragon, Sheep, Dog and Ox Day 1 Mewa is Red 7
Month Snake, Monkey, Pig and Tiger Day 1 Mewa is White 1
Month Horse, Bird, Mouse and Rabbit Day 1 Mewa is Green 4