Stardate Format:

Year = # of Billion, (13) followed by Earth Year - 1000 (990 for 1990)

Month = Month #/12 * 100 IE August = 8/12 = 66

Date = Date / Total Days per Month * 100 IE 8 = 25

Hour = Time / 24 *100 = 22/24 = 91 

13990.66.25.91