Petrol or gasoline is assessed, categorised and sold by an octane rating. Generally, in most areas of the world, the Research Octane Number (RON) is used, but in North America, the Anti-Knock Index (AKI) is used. Conventional 'standard' "Super Unleaded" petrol in Europe, South Asia and Australia has an octane rating of 95 RON, and in North America "Premium Unleaded" is AKI/RdON/PON 91-93 (RON 96–98). However, higher octane "Super Plus Unleaded" - often formulated with higher quality additives, is usually set at around 98 RON in mainland Europe; but this can vary by market. Most oil/petroleum companies now 'market' their own Super Plus Unleaded petrols under a unique name - and the current name for Shell Super Unleaded fuel is "V-Power". Like most Super Plus Unleaded petrols, V-Power also contains higher concentrations of detergents and other additives to help clean the engine and smooth its operation.[2] In the United States (U.S.), around 2004, all U.S. Shell "Premium" gas was rebranded as "V-Power". In 2015, Shell re-branded V-Power to the newly launched V-Power Nitro+.[7] In Canada, from June 2005, Shell Canada re-branded Optimax Gold to V-Power. In 2015, Shell Canada re-branded V-Power to V-Power Nitro+.[8] In Canada, Shell V-Power NiTRO+ premium gasoline does not contain ethanol.[9] In Hong Kong, as there is no oil refinery plant located in Hong Kong, Gasoline was imported from Singapore, which is 98 RON. However, V-Power sold in gas stations rumored reach 167 RON (the highest native RON for consumer grade commercial petrol across worldwide). Such figure is not supported by actual test, nor is it confirmed by Shell and which is contradicted from a reading material for Legislators of Legislative Council.[10] In New Zealand, from 2007, Shell rebranded 95 Premium Unleaded as V-Power. It was still rated at 95 RON. Shell sold its New Zealand retail operations in 2010, to a consortium which later became Z Energy, and upon re-branding Shell V-Power was replaced with ZX Premium Unleaded. In Sweden, Shell V-Power was previously 99 RON, but is now been re-branded under the new owner St1 from June 2011, to "Shell V-Power E5" making it 98 RON with a mix of 5% ethanol.[11] In Argentina, from 2009, Shell rebranded 95 Super fuel as V-Power and also the Diesel premium for V-Power diesel.[citation needed] In the Philippines, Pilipinas Shell launches the new Shell V-Power (replacing Shell Velocity) in 2006. On June 1, 2012, Shell Philippines launches the premium fuel grade, Shell V-Power Nitro+ Gasoline (formerly Shell Super Premium) and Shell V-Power Nitro+ Racing (formerly Shell V-Power). In Indonesia, from April 2013, Shell rebranded 95 Super Extra as V-Power with additional additives. While it is still rated at 95 RON. In Malaysia, it is RON97 but in Singapore, where Shell offers RON98, the octane is higher for V-Power Racing. In Philippines, on June 8, 2017, V-Power Nitro+ was replaced with V-Power with Dynaflex technology.[12] In Russia, all Shell stations offer V-Power rated 95 RON, some stations also offer V-Power Racing (98 RON).