Write SQL query to solve given problem: Which NBA team that didn't play in playoffs had the most winning rate in the 2000 NBA regular season?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT T2.tmID FROM players_teams AS T1 INNER JOIN teams AS T2 ON T1.tmID = T2.tmID AND T1.year = T2.year WHERE T1.PostGP = 0 AND T1.year = 2000 ORDER BY CAST(T2.won AS REAL) / (T2.won + T2.lost) DESC LIMIT 1