public static function getDistanceX(PHPExcel_Worksheet $sheet, $startColumn = 'A', $startOffsetX = 0, $endColumn = 'A', $endOffsetX = 0)
	{
		$distanceX = 0;

		// add the widths of the spanning columns
		$startColumnIndex = PHPExcel_Cell::columnIndexFromString($startColumn) - 1; // 1-based
		$endColumnIndex = PHPExcel_Cell::columnIndexFromString($endColumn) - 1; // 1-based
		for ($i = $startColumnIndex; $i <= $endColumnIndex; ++$i) {
			$distanceX += self::sizeCol($sheet, PHPExcel_Cell::stringFromColumnIndex($i));
		}

		// correct for offsetX in startcell
		$distanceX -= (int) floor(self::sizeCol($sheet, $startColumn) * $startOffsetX / 1024);

		// correct for offsetX in endcell
		$distanceX -= (int) floor(self::sizeCol($sheet, $endColumn) * (1 - $endOffsetX / 1024));

		return $distanceX;
	}