Your natal horoscope born in Chennai is pretty powerless and Moon is the only beneficial planet while all others are malefic. But since you are now in US, these natal strengths could change considerably due to transit influences. To answer your question, the natal horoscope has to be computed at your place of residence in USA. Read my blog http://www.navagrahastro.blogspot.com and come through Paid consultation with your current place of residence in US.
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