Question: The 2017–18 Serie B (known as the Serie B ConTe.it for sponsorship reasons) is the 86th season since its establishment in 1929, a total of 22 teams are contesting the league: 15 returning from the 2016–17 season, The 2016–17 Serie B, known as the Serie B ConTe.it for sponsorship reasons, and was the 85th season since its establishment in, what year?
Sentence (from "2016–17 Serie B"): A total of 22 teams were contesting the league: 15 returning from the 2015–16 season, 4 promoted from Lega Pro, and 3 relegated from Serie A.
Relevant evidence: No