The Swiss Ice Hockey Federation designates the following levels : using terms from the national languages of Switzerland. In the United States, USA Hockey designates the following levels:  Girls hockey operates under their own age classifications, namely 10U, 12U, 14U, 16U and 19U. Many organizations and leagues that have larger numbers of registered players tend to delineate within the two-year window allowed for each age group. In these situations, teams composed entirely or primarily of players in their second year of eligibility are designated 'major' teams, while those with players in their 1st year of eligibility are designated "minor" teams. (For example, ten-year-olds would be "squirt majors" while nine-year-olds would be "squirt minors".) This is especially true in "AAA". Some leagues separate players six years old and younger into their own group, often referred to using names like "Mini-Mites", "Mosquitoes", or "Microns." USA Hockey designates four skill levels:  The Amateur Athletic Union has returned to licensing the sport of ice hockey. During the 2011–2012 season the AAU began licensing junior and youth leagues as well. The Western States Hockey League (WSHL) moved their operations from USA Hockey into AAU and Hockey Michigan was formed, providing Mite (8-and-under) conventional full-ice playing opportunities in the face of cross-ice mandates adopted by the USA Hockey district affiliate. During the 2012–2013 season, AAU junior and youth operations expanded rapidly and currently span coast to coast. Although some AAU clubs still use classification terms such as "mites" or "midgets", the official AAU youth designations indicate the age group with the format "xU", where "x" is the maximum age number and the "U" indicates "and under". Officials for youth hockey are often youth players themselves, calling games in lower levels than the one they participate in themselves. Just as players start out playing youth hockey, officials start their officiating career officiating youth hockey, making it up through the ranks as their officiating skill increases. USA Hockey defines certain levels of their officials and so does Hockey Canada and the International Ice Hockey Federation. Currently, many youth officials quit after a few games, mainly due to verbal abuse from parents, coaches and players. The other issue faced by young referees is a reluctance from older officials to give them more advanced games. In the US and Canada, news stories pop up from now and then that describes physical abuse on youth officials, in addition to verbal abuse.