I guess we lose 1% Elo everyday. Doesn't matter if you gain the Elo for the day or not. We gain more Elo and lose less until 4000, after 4000 we lose more and gain less. example at 2000Elo we gain 10Elo per kill and lose 1Elo per death whereas after 4000 we gain 5Elo per kill and lose 10Elo per death. Elo updates after rejoin in every mode not just Duel .
