Usually Bitcoin is measured in dollars to increase the value of its investment because the dollar is one of the most popular and powerful currencies in the world, but you can choose your own currency if the dollar is not your currency. There are many choices on coinmarketcap.com.
Bitcoin is clearly independent, because not relying on paper money, wherever it is used, will be converted to the price of the country's currency. For example, bitcoin is used in the UK, this will convert 1 bitcoin worth how much poundsterling. In other countries it is also the same in national currency. Why should it be assessed with fiat currency, because bitcoin is not valued by goods. When assessed by goods, the value is ambiguous.