What was the oil price in China when the international crude oil price was $80?

I don't know the oil price: in June 2008, the international oil price 130 USD/barrel (RMB/USD, about 900 yuan/barrel), 93# gasoline 6 yuan/liter; 20 12 March international oil price 108 USD/barrel (RMB/USD exchange rate, about 680 yuan/barrel), 93# gasoline price 8 yuan/liter. After deducting the price difference of fuel tax reform, the oil price reached 7 yuan/liter in March 20 12. I really can't read these data! According to the comparable price: 900/6=680/x x=4.53, the international oil price in March of 20 12 is 108 USD/barrel, and the reasonable domestic oil price of 93# gasoline should be in 5.7 yuan/liter; I wonder if the above calculation is correct. If it's wrong, don't laugh!