condition mean min max ZT0-3 4.4176025 4.236475 4.59873 ZT4-7 3.182625 3.182625 3.182625 ZT8-11 3.1619900000000003 3.1619900000000003 3.1619900000000003 ZT12-15 0 0 0 ZT16-19 4.10665 4.10665 4.10665 ZT20-23 3.770455 3.770455 3.770455