Oct 27 (Reuters) - The Slovak central bank's foreign currency reserves dropped to $13.021 billion in the week to Oct. 25, from $13.062 billion one week earlier, the bank said on Friday. SLOVAK FOREIGN RESERVES OCT 25 OCT 18 OCT 11 ($ million) Central Bank 13,021.2 13,061.5 13,081.8 Commercial banks 2,461.5 2,321.4 2,625.9 Total banking sector 15,482.7 15,382.9 15,707.7 NOTE: Reserves data are calculated according to methodology compatible with European Central Bank standards. (Reporting by Martin Santa in Bratislava) ((Editing by David Christian-Edwards; editorial@reuters.sk; Reuters Messaging: martin.santa.reuters.com@reuters.net; +421 2 5341 8402)) Keywords: MARKETS SLOVAKIA RESERVES