I've had the same Medicare advantage plan with Kaiser in Colorado since 2019: My monthly costs for Kaiser, and then for Medicare part B:
2019: 370.50 135.50
2020: 360.50 144.60
2021: 294.50 148.50
2022: 236.50 170.10
2023: 236.50 164.90
2024: 236.50 ??
Before 2019 I had a different plan. I was retired but not yet eligible for medicare. Prices for such pre-medicare plans have increased significantly over this period. edit fix formatting