How do you calculate the conversion rate of the prices?

The currencies are updated daily by a program which scans the inter bank rates of the day from a website that is run by the Financial Times in London and converts the base currency (the currency at the top of the prices list and indicated by the property owner when building their advertisement), into the other two currencies shown below.

To find currencies other than those published, click on the Currency converter link in the menu bar on the left of the page.