condition mean min max ZT0-3 9.964275 9.964275 9.964275 ZT4-7 11.198034499999999 11.198034499999999 11.198034499999999 ZT8-11 9.263423 9.263423 9.263423 ZT12-15 9.4791385 9.4791385 9.4791385 ZT16-19 9.838465 9.838465 9.838465 ZT20-23 10.530850000000001 10.530850000000001 10.530850000000001