Yuki for boys didn't make to the top 1000 in 2014 but for the girls, the most popular kanji used for Yuki is 由紀 which is in 255th place, followed by 有紀 (400th), 有希 (404th), 友紀 (475th), 優希 (536th), 由貴 (787th) and 雪 (958th). Yuki, using the phonetic characters (ゆき) is in 974th place.Yuki for girls has fallen in popularity (except the one with 雪) in recent years.Popularity sources: http://5go.biz/sei/cgi/ninki2.htm & http://www.namaejiten.com/h01/girl01.html.