Rc - average rating of rated opponents, Ro - rating of a player in a tournament, Rp - rating performance of an unrated player, W - points won in a tournament against rated opponents, N - total number of games against rated opponents, Change - change used for calculation according to formula, K - development coefficient, Kchg - rating change of a player calculated as (K * change)
Orellana Zambrano, Naudys Wencesl 
