Dear Master Lee, I have an enquiry on the method in which the Gua Number ("Personal Number). Please correct me if I am wrong in the calculation. For example, if I am born in 1971 after Li Chun. My Gua number is 2 or Trigram Kun. The formula to calculate the Gua are: For Male , Gua Number = 10 - X where X is the sum of the last two digits of your birth year, added until you get a single digit. so X = 7 + 1 = 8. My question : Why is our Gua number determine using the Geogian calander with a baseline dated back 1971 years ago ? And adding the last 2 digit has somewhat dissociated the original quality of the year number (so that 8 has no correlation with 71)? Should not we take a starting date from a change in government, for example, because a change in ruler, in general has an major impact on the lifestyle of its citizen ? (Example, from Ching Dynasty - I just started reading up on Fengshui Principle only last Saturday. If there is a previous posting on this matter please help to direct the link. Thank you. Rgds, Andrew.