condition mean min max ZT0-3 11.990499 11.990499 11.990499 ZT4-7 10.553362 10.553362 10.553362 ZT8-11 10.196409 10.196409 10.196409 ZT12-15 12.9786945 12.9786945 12.9786945 ZT16-19 9.3308565 9.3308565 9.3308565 ZT20-23 13.646189 13.646189 13.646189