Here are the peaks and valleys over the past 26 years for various Illinois metro areas. They're specific to each metro during the two main recessions and recoveries over this period. For instance some areas like Carbondale grew from 1990 right through 2007 before shifting course:
Bloomington:
1990: 80,147
1999: 98,385
2004: 89,094
2010: 97,397
2016: 92,828
Carbondale:
1990: 53,185
2007: 65,670
2013: 53,981
2016: 55,713
Champaign:
1990: 106,910
2007: 116,469
2016: 113,128
Chicago CSA
1990: 4,011,176
2000: 4,559,774
2003: 4,344,274
2007: 4,644,986
2010: 4,358,407
2016: 4,673,495
Danville:
1990: 38,755
2016: 32,721
Davenport/Quad Cities:
1990: 179,456
1998: 193,328
2003: 184,104
2007: 197,330
2016: 178,637
Illinois piece of Quad Cities:
1990: 104,081
2007: 111,778
2015: 98,815
Decatur:
1990: 56,438
2016: 46,447
Elgin:
1990: 203,709
2007: 313,996
2010: 288,213
2015: 303,637
Kankakee:
1990: 45,815
2007: 52,393
2015: 52,248
Lake County:
1990: 340,155
2007: 434,729
2009: 404,607
2015: 430,958
Peoria:
1990: 175,473
1998: 191,152
2003: 169,492
2007: 194,558
2015: 172,838
Rockford:
1990: 151,453
1999: 166,477
2003: 148,824
2007: 165,348
2015: 159,269
Springfield:
1990: 106,179
2015: 106,872
Illinois piece of St Louis:
1990: 301,300
2000: 321,181
2003: 307,360
2007: 333,230
2009: 310,760
2015: 322,824
Illinois is fairly stagnant except for Chicago, but even that isn't going above and beyond its previous peaks outside downtown Chicago.
Just looking at a few cities in Iowa doing well, they have definite momentum that Illinois just doesn't.
Iowa City:
1990: 65,926
2016: 95,017
Cedar Rapids:
1990: 111,117
2016: 140,100
Des Moines:
1990: 230,261
2016: 332,303
One that's good to see is Detroit finally waking up. They had a slow burn from 2000 straight through 2007, then a bust through 2010, but finally are gaining back jobs:
Detroit:
1990: 1,945,607
2000: 2,216,021
2004: 2,050,260
2007: 1,998,781
2010: 1,772,626
2016: 1,950,213
Michigan in general is recovering:
1976: 3,618,361
2000: 4,976,322
2007: 4,658,939
2010: 4,194,041
2016: 4,612,036
Illinois:
1976: 4,808,498
2000: 6,211,404
2007: 6,334,010
2010: 5,937,047
2016: 6,197,757