The economy is projected to have grown by an average of 0.5 percent in the July-September quarter compared with the previous quarter, according to eight major private-sector think tanks.

The growth in gross domestic product would mark a second straight quarter-on-quarter rise and translate into an annualized expansion of 1.9 percent, the think tanks said.

Most of the think tanks believe that exports, one of the factors capable of sparking economic growth, will have slowed in the quarter after serving as Japan's sole driving force for months.