condition mean min max ZT0-3 21.84346 21.84346 21.84346 ZT4-7 26.3261775 26.3261775 26.3261775 ZT8-11 21.465532500000002 21.465532500000002 21.465532500000002 ZT12-15 18.271497 18.271497 18.271497 ZT16-19 19.689218 19.689218 19.689218 ZT20-23 21.5589455 21.5589455 21.5589455