UPDATE 1-Japan's new math seen adding $129 bln to GDP - Nikkei

Dec 8 (Reuters) - The Japanese Cabinet Office is changing its method to measure gross domestic product (GDP), in a move that is expected to add 5-10 trillion yen ($64.33-$128.65 billion) to the country's nominal GDP, business daily Nikkei reported.

The new method -- to be used for the revised July-Sept GDP figures due on Friday -- may beat a price-adjusted 5.3 percent growth that private-sector economists predicted the government would report, the newspaper said.

The new method counts the interest rate spread that banks and other financial institutions profit from as added value under financial intermediation services, Nikkei reported.

Corporate software developed for in-house use would be seen as capital expenditure, the daily said.

GDP as far back as the April-June quarter would be recalculated, Nikkei said.