I have a question that I hope some of you out there can help me understand the concept better.

When a person's horoscope is drawn up, the Birth Chart gives the general reading of life of the native ahead of him. As the person grows up. the native moves from the place of birth. In later years, say at age 30, when the native's horoscope is being read should his current physical location be taken for the transit calculation or the transit calculation should be based on the original birth place coordinates? For example, a person was born in Delhi, India but is now in San Francisco, USA. When the ancient sages discovered the use of horoscope, mobility was not a big consideration as people didn't travel far from teir place of birth.
Thanks
