How accurate are SER-AR's polls?

ELECTIONSER-AR POLLACTUAL RESULT
2023-05-28 Cumhurbaşkanlığı 2. Tur
Erdoğan: 48.7%
Kılıçdaroğlu: 51.3%
Erdoğan: 52.18%
Kılıçdaroğlu: 47.82%
2023-05-14 Cumhurbaşkanlığı 1. Tur
Erdoğan: 45.2%
Kılıçdaroğlu: 52.1%
Oğan: 2.7%
Erdoğan: 49.52%
Kılıçdaroğlu: 44.88%
Oğan: 5.17%
2023-05-14 Genel Seçim
Cumhur: 43.5%
Millet: 39.7%
Emek: 14.6%
Cumhur: 49.49%
Millet: 35.04%
Emek: 10.55%