public static function subtractCentury($ts = null, $num = 1)
	{
		return sfTime::subtract($ts, $num, sfTime::CENTURY);
	}
public static function subtractCentury($ts = null, $num = 1)
	{
		return sfTime::subtract($ts, $num, sfTime::CENTURY);
	}
public static function subtractCentury ( $ ts = null , $ num = 1 ) { return sfTime :: subtract ( $ ts , $ num , sfTime :: CENTURY ) ; }
Subtracts the specified number of centuries from the timestamp.

@param	timestamp
@param	int
@return	timestamp
Subtracts the specified number of centuries from the timestamp .