condition mean min max ZT0-3 3.3990725 3.3083150000000003 3.48983 ZT4-7 2.240665 2.240665 2.240665 ZT8-11 4.66164 4.66164 4.66164 ZT12-15 0 0 0 ZT16-19 5.4939350000000005 5.4939350000000005 5.4939350000000005 ZT20-23 5.710185 5.710185 5.710185