County data from the released 2022 Census estimates for the core counties of Great Lakes and adjacent Rust Belt cities. I included last year's 2021 estimate along with the revised 2021 estimate, as there are a few significant changes in last years estimates.
These may be a preview of how the core cities are going to fare when the numbers are released later this year.
Chicago (Cook County)
2020 Census - 5,275,541
2021 Original Estimate - 5,173,146 (-102,395 from 2020, -1.94%)
2021 Revised Estimate - 5,177,606 (-97,935 from 2020, -1.86%)
2022 Estimate - 5,109,292 (-68,314 from 2021, -1.32%)
Detroit (Wayne County)
2020 Census - 1,793,561
2021 Original Estimate - 1,774,816 (-18,745 from 2020, -1.05%)
2021 Revised Estimate - 1,773,073 (-20,488 from 2020, -1.14%)
2022 Estimate - 1,757,043 (-16,030 from 2021, -0.9%)
Cleveland (Cuyahoga County)
2020 Census - 1,264,817
2021 Original Estimate - 1,249,387 (-15,430 from 2020, -1.22%)
2021 Revised Estimate - 1,247,808 (-17,009 from 2020, -1.34%)
2022 Estimate - 1,236,041 (-11,767 from 2021, -0.94%)
Milwaukee (Milwaukee County)
2020 Census - 939,489
2021 Original Estimate - 928,059 (-11,430 from 2020, -1.22%)
2021 Revised Estimate - 924,207 (-15,282 from 2020, -1.63%)
2022 Estimate - 918,661 (-5,546 from 2021, -0.6%)
Buffalo (Erie County)
2020 Census - 954,236
2021 Original Estimate - 950,684 (-3,553 from 2020. -0.37%)
2021 Revised Estimate - 954,350 (+114 from 2020, +0.01%)
2022 Estimate - 950,312 (-4,038 from 2021, -0.42%)
Rochester (Monroe County)
2020 Census - 759,443
2021 Original Estimate - 755,160 (-4,283 from 2020, -0.56%)
2021 Revised Estimate - 756,547 (-2,896 from 2020, -0.38%) 7
2022 Estimate - 752,035 (-4,512 from 2021, -0.6%)
Pittsburgh (Allegheny County)
2020 Census - 1,250,578
2021 Original Estimate - 1,238,090 (-12,488 from 2020, -1.0%)
2021 Revised Estimate - 1,245,445 (-5,133 from 2020, -0.41%)
2022 Estimate - 1,233,253 (-12,192 from 2021, -0.98%)
Cincinnati (Hamilton County)
2020 Census - 830,639
2021 Original Estimate - 826,139 (-4,500 from 2020, -0.54%)
2021 Revised Estimate - 827,501 (-3,138 from 2020, -0.38%)
2022 Estimate - 825,037 (-2,464 from 2021, -0.3%)
St. Louis (St. Louis city)
2020 Census - 301,578
2021 Original Estimate - 293,310 (-8,286 from 2020, -2.74%)
2021 Revised Estimate - 293,562 (-8,016 from 2020, -2.66%)
2022 Estimate - 286,578 (-6,984 from 2021, -2.38%)
If St. Louis continues on its current track it may fall below Buffalo's population within this decade.