TOKYO, June 7 (Reuters) - The Nikkei share average slid into bear market territory on Friday but ended the day just out of it on expectations that the the country's public pension fund will increase its weighting of Japanese equities. The Nikkei finished down 0.2 percent at 12,877.53. At one point, it fell as low as 12,548.20, down 21.3 percent from a multi-year peak hit on May 23 but later rose as high as as 13,106.20 after the government flagged a briefing on its public pension fund. Japan's Government Pension Investment Fund (GPIF), the world's largest public pension fund with more than $1 trillion of assets, announced after the bell that it would increase its target allocation for Japanese stocks to 12 percent from 11 percent. The Topix dropped 1.3 percent to 1,056.95.