"Judges generally have been awarding joint custody more often, but that still represented only 15 percent of the time by 2007, statistics show. The time of custody has been growing more equal, however. Arizona is a leader on a change toward more sharing of custody time. The old standard of every other weekend and one night a week for the non-custodial parent means about 20 percent of the time. Some states now require at least 40 percent for each parent."