These statistics were provided by John Gomez of Kizuna-CPR (http://kizuna-cpr.org/meeting_summary_november_24_2012):

“4.6 million divorces 1992 – 2010, one child per divorce on average, 58% loss of access according to NHK Close Up Gendai yields an estimated 2.7 million children in Japan who have lost their relationship with their parent during this time, which is a human rights violation. It is about 150,000 children per year.”
That means every hour an additional 17 children living in Japan are being shut out of the life of one of their parents.  Considering the cumulative impact, not just in terms of the number of children involved, but also left-behind parents, family members, and others, this problem is having a devastating effect on a sizeable percentage of the Japanese population.