TOKYO, Dec 29 (Reuters) - Japan's Nikkei share average erased early modest gains and ended slightly lower on its final trading day of the year on Friday, but the index still gained nearly 20 percent in 2017.
The Nikkei ended the day down 0.08 percent at 22,764.94 points, while the broader Topix was also down 0.08 percent at 1,817.56.
Advancers outnumbered decliners 332 to 266, with 64 issues ending unchanged.
The stronger global economy, as well as domestic political stability and the Bank of Japan's ultra-easy monetary policy helped lift Japanese corporate earnings in 2017, which in turn helped push the Nikkei up 19.1 percent and the Topix up 19.7 percent.
For the week, the Nikkei edged down 0.6 percent as investors took profits ahead of year-end. But it was up 0.2 percent for December.
On Friday, the banking subindex was 0.7 percent higher, recouping some of its 1.4 percent fall in the previous session. Mitsubishi UFJ Financial Group gained 1.2 percent.
SoftBank Group Corp gave up earlier gains and finished 0.1 percent lower after news on Thursday that a SoftBank-led consortium will buy a large number of shares of Uber Technologies Inc in a deal that values the ride-services firm at $48 billion.
Asahi Glass Co shares rose 2 percent after the Nikkei business daily reported that the company is expected to post an operating profit of around 125 billion yen for its fiscal year through Dec. 31.
(Reporting by Lisa Twaronite; Editing by Richard Borsuk and Kim Coghill)