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|View History: Monthly Download Data (XLS File)                      
|View History: Monthly                                                
|View History: Monthly                                                
|View History:                                                        
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|Illinois Natural Gas Underground Storage Volume  (Million Cubic Feet)
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|Illinois Natural Gas Underground Storage Volume  (Million Cubic Feet)
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|Year                                                                                                                              | Jan     | Feb     | Mar     | Apr     | May     | Jun     | Jul     | Aug     | Sep     | Oct     | Nov     | Dec    
|--------------------------------------------------------------------------------------------------------------------------------- | ------- | ------- | ------- | ------- | ------- | ------- | ------- | ------- | ------- | ------- | ------- | -------
|1990                                                                                                                              | 806,109 | 754,941 | 721,785 | 717,863 | 749,618 | 782,498 | 812,054 | 847,731 | 881,760 | 900,526 | 903,640 | 870,265
|1991                                                                                                                              | 801,635 | 753,141 | 727,699 | 720,275 | 751,641 | 781,883 | 810,535 | 844,477 | 877,485 | 904,206 | 885,341 | 851,258
|1992                                                                                                                              | 791,129 | 743,484 | 716,909 | 709,150 | 742,812 | 774,578 | 805,097 | 843,543 | 878,334 | 905,597 | 887,454 | 844,108
|1993                                                                                                                              | 783,875 | 735,236 | 710,377 | 713,214 | 746,899 | 779,762 | 810,546 | 844,320 | 882,456 | 907,957 | 898,655 | 854,691
|1994                                                                                                                              | 781,826 | 737,719 | 723,108 | 722,735 | 746,576 | 776,189 | 808,832 | 843,372 | 880,762 | 907,622 | 898,872 | 866,846
|                                                                                                                                 
|1995                                                                                                                              | 803,422 | 745,457 | 721,311 | 716,886 | 745,970 | 774,803 | 804,912 | 837,002 | 868,941 | 899,868 | 885,665 | 841,580
|1996                                                                                                                              | 773,947 | 732,685 | 709,630 | 712,583 | 739,780 | 772,171 | 807,996 | 841,476 | 878,415 | 907,151 | 891,217 | 855,168
|1997                                                                                                                              | 790,465 | 750,261 | 726,546 | 726,747 | 750,612 | 779,018 | 812,103 | 848,305 | 884,993 | 913,298 | 911,830 | 866,355
|1998                                                                                                                              | 808,336 | 772,264 | 744,105 | 744,442 | 767,644 | 796,225 | 823,688 | 855,332 | 888,703 | 917,775 | 908,314 | 866,569
|1999                                                                                                                              | 803,099 | 762,767 | 736,006 | 725,051 | 750,990 | 776,900 | 803,226 | 836,475 | 873,229 | 904,849 | 901,967 | 861,663
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|2000                                                                                                                              | 803,971 | 768,567 | 759,792 | 746,785 | 760,079 | 793,239 | 821,964 | 850,357 | 881,988 | 916,536 | 891,307 | 841,321
|2001                                                                                                                              | 798,282 | 754,643 | 739,892 | 748,331 | 782,723 | 808,660 | 829,002 | 852,681 | 886,203 | 912,244 | 935,824 | 888,056
|2002                                                                                                                              | 830,218 | 780,402 | 753,411 | 744,594 | 770,771 | 808,248 | 836,701 | 873,055 | 911,579 | 941,298 | 921,893 | 869,667
|2003                                                                                                                              | 799,243 | 748,903 | 738,046 | 746,852 | 776,051 | 808,658 | 841,001 | 871,264 | 904,343 | 936,561 | 921,984 | 878,513
|2004                                                                                                                              | 813,120 | 768,342 | 735,771 | 736,509 | 764,091 | 798,542 | 833,337 | 867,426 | 906,402 | 936,941 | 922,483 | 870,619
|                                                                                                                                 
|2005                                                                                                                              | 804,552 | 756,636 | 727,814 | 726,018 | 755,015 | 789,514 | 825,617 | 862,635 | 900,933 | 934,712 | 923,785 | 871,161
|2006                                                                                                                              | 826,369 | 767,973 | 737,607 | 736,325 | 762,616 | 795,214 | 829,024 | 865,193 | 904,795 | 938,544 | 925,199 | 878,607
|2007                                                                                                                              | 810,221 | 755,998 | 745,161 | 740,395 | 770,783 | 802,452 | 836,366 | 869,804 | 908,985 | 944,118 | 924,871 | 873,189
|2008                                                                                                                              | 804,939 | 750,522 | 730,023 | 730,071 | 755,610 | 791,731 | 826,474 | 866,811 | 906,275 | 942,126 | 928,681 | 874,106
|2009                                                                                                                              | 811,444 | 764,775 | 739,744 | 736,116 | 766,976 | 804,142 | 836,345 | 874,904 | 915,815 | 952,865 | 942,592 | 887,616
|                                                                                                                                 
|2010                                                                                                                              | 820,108 | 766,552 | 745,296 | 752,935 | 782,948 | 814,732 | 842,086 | 877,768 | 916,368 | 955,989 | 945,503 | 892,450
|2011                                                                                                                              | 819,896 | 767,423 | 737,451 | 743,002 | 770,943 | 804,883 | 836,217 | 876,263 | 915,255 | 953,600 | 951,405 | 897,705
|2012                                                                                                                              | 830,675 | 775,259 | 759,933 | 757,641 | 786,110 | 816,228 | 847,448 | 886,296 | 922,131 | 958,191 | 950,711 | 900,410
|2013                                                                                                                              | 831,409 | 770,598 | 744,252 | 746,993 | 774,859 | 809,958 | 842,081 | 878,487 | 917,781 | 952,936 | 945,007 | 888,196
|2014                                                                                                                              | 816,002 | 766,281 | 742,400 | 743,678 | 773,333 | 808,673 | 844,091 | 883,325 | 922,213 | 960,979 | 949,775 | 898,864
|                                                                                                                                 
|2015                                                                                                                              | 835,335 | 777,231 | 756,099 | 754,994 | 783,708 | 813,749 | 846,434 | 880,855 | 918,466 | 955,422 | 956,585 | 911,046
|2016                                                                                                                              | 841,442 | 791,168 | 765,076 | 760,530 | 786,818 | 818,890 | 847,330 | 880,865 | 922,690 | 960,573 | 959,750 | 906,505
|2017                                                                                                                              | 847,117 | 804,200 | 769,237 | 764,802 | 782,323 | 814,711 | 839,891 | 874,446 | 916,235 | 956,652 | 957,087 | 899,672
|2018                                                                                                                              | 834,975 | 791,969 | 760,916 | 753,147 | 773,408 | 803,535 | 832,289 | 867,033 | 910,190 | 953,580 | 948,561 | 904,497
|2019                                                                                                                              | 832,749 | 787,756 | 766,030 | 768,505 | 797,755 | 829,760 | 851,558 | 885,672 | 925,887 | 965,818 | 963,352 | 922,831
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|2020                                                                                                                              | 870,316 | 815,019 | 780,377 | 772,780 | 790,788 | 819,703 | 849,139 | 889,504 | 930,391 | 968,800 | 972,952 | 927,875
|2021                                                                                                                              | 868,446 | 819,854 | 788,415 | 778,697 | 793,688 | 820,279 | 845,530 | 880,486 | 926,207 | 970,979 | 971,846 | 926,890
|2022                                                                                                                              | 853,529 | 807,454 | 777,074 | 773,505 | 791,340 | 818,493 | 848,974 | 883,600 | 923,026 | 968,429 | 963,523 | 917,793
|2023                                                                                                                              | 869,870 | 818,612 | 782,488 | 776,024 | 791,400 | 818,540 | 846,635 | 880,380 | 920,261 | 966,352 | 973,339 | 931,779
|2024                                                                                                                              | 866,182 | 818,385 |         |         |         |         |         |         |         |         |         |        
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|- = No Data Reported;  -- = Not Applicable;  NA = Not Available;  W = Withheld to avoid disclosure of individual company data.
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|Release Date: 4/30/2024                                                                                                          
|Next Release Date: 5/31/2024