Task: Question Understanding
Input (English): Passage: From February 1995 to January 2005, the Chairman of the unicameral Supreme Assembly of Uzbekistan was Erkin Khalilov, who had been Acting Chairman of the Supreme Soviet from 1993 to 1995. Since 2005 the Senate and Legislative Chamber have each had their own presiding officer.
Question: How many years was Erkin Khalilov Acting Chairman of the Supreme Soviet?
Output (English): number