County bbl % of total 1. Ellis 3,325,892 6.9 2. Finney 2,881,621 6.0 3. Russell 2,791,097 5.8 4. Rooks 2,357,332 4.9 5. Barton 2,111,467 4.4 6. Ness 1,992,089 4.1 7. Butler 1,847,366 3.8 8. Stafford 1,783,444 3.7 9. Seward 1,668,075 3.4 10. Graham 1,448,376 3.0
County bbl 1. Butler 560,096,766 2. Barton 504,593,587 3. Russell 492,690,756 4. Ellis 439,438,883 5. Rice 326,830,817 6. Greenwood 292,207,888 7. Stafford 247,314,568 8. Rooks 217,062,850 9. McPherson 201,390,445 10. Cowley 172,982,091
These data are adapted from the work of Douglas L. Beene, Kansas Geological Survey.