The traditional New Year dinner for the imperial house was composed of 99 dishes since the number 9 is an auspicious number! The number 9 was historically associated with the Emperor of China; the Emperor's robes often had nine dragons, and Chinese mythology held that the dragon has nine children. Moreover, the number 9 in Chinese sounds like the word for "long lasting" and as such is often used in weddings.
Other lucky numbers are 6 and 8. Number 6 is considered good for business and also represents happiness. Number 8 in Chinese sounds similar to the word which means "prosper" or “wealth”.