In all open societies prices are left to the market forces to determine. Of course, you must allow people who gamble on the stock exchange and could influence the price. Cost of water and a few other utilities is controlled by some sort of Ombudsman. The point is the customer is trapped and they have no choice, thus an independent body should oversee the price rise.

In the oil-producing countries price is controlled by the government and generally, their nations are very sensitive to the retail price rise. Thus, you will see ridiculous prices of a gallon of petrol expressed by the value of their currency.

Thank you sirous yasseri sir for your valuable insights.

Well,

Density is an important property for pricing crude oil and light crude, preferably because it is rich in low-carbon hydrocarbon separators (gazolin).

The quality function of crude oil is [American Petroleum Institute (API) gravity]

Degrees API gravity = (141.5 / ρw) - 131.5, where ρw: density of water at 15.6 ° C = 1 gm / cm3.

API gravity of water = (141.5 / 1) - 131.5

API gravity of water = 10 degrees

For light crudes, (density less than 0.870 g / cm3).

         The API gravity is higher than 31.1 degrees.

For medium crudes, (density between 0.870 and 0.920 g / cm3).

         The API gravity is between 22.3 and 31.1 degrees.

For heavy crudes, (density above 0.920 g / cm3).

         The API gravity is below 22.3 degrees

Regards