This paper presents a new monthly value-weighted, all-share total return index for the Finnish stock market. The index covers the period from the establishment of the Helsinki Stock Exchange in October 1912 to the beginning of 1970, after which another index becomes available. When combined, they can be used to study continuously the development of the Finnish equity market from the beginning of the stock exchange until the present day. We also provide a detailed description of the construction methodology and a comparison between our index and those available earlier. The index replaces the Unitas price index which has been the only index available for long-term studies from 1928 onwards. The new index also provides an alternative to the book equity weighted Poutvaara (1996) price index for the period 1912-1929. © 2009 Elsevier B.V.