Τhe GER30, also known as DAX or Deutscher Aktien Index, is a stock index that represents 40 of the largest and most liquid German companies that trade on the Frankfurt Exchange. The prices used to calculate the GER30 index come through Xetra, and a free-float methodology is used to calculate the index weightings together with a measure of the average volume.
As a blue-chip index, the GER30 is weighted by market capitalisation, so companies with higher market capitalisation have more impact on its value. Companies included in the GER30 can have a maximum weight of 10%. The prices used to compute the Index come from Xetra, which is an electronic trading system.
The GER30 was created in 1988, and member companies represent roughly 80% of the aggregate market cap that trades on the Frankfurt Stock Exchange. In 2021 the companies expanded from 30 to 40 in total.