THE value of companies quoted on the Irish Stock Exchange would jump by about seven per cent from January 1997, when listed companies from Northern Ireland would be included in the ISEQ Index for the first time.

Companies from Northern Ireland which are already listed on the Irish Stock Exchange are to be included in the ISEQ Index of shares from January 1st 1997, the lSE announced yesterday.

Eight companies from Northern Ireland are already listed on the Stock Exchange in Dublin and their share prices are printed in the newspapers every day. But their absence from the ISEQ Index means that they are not included when the ISE calculates the value of the market and movements.

At the moment, the movements in the share prices of these companies have no impact on the value of the market and therefore do not influence the index.

The market capitalisation - the value of the companies listed - is currently about £19 billion. The inclusion of the eight Northern Ireland companies will add about £1.3 billion to the value of the market at current prices.

The companies to be added to the lSEQ Index are Northern Ireland Electricity, UTV, Ewart, Boxmore, Hampden, Mackey, Powerscreen and Lamont.

ISE chief executive Mr Tom Healy said the inclusion of the companies in the Index will make them more attractive to Irish investors and should encourage more companies from Northern Ireland to seek listings in Dublin.