condition mean min max ZT0-3 4.8127975 4.167415 5.4581800000000005 ZT4-7 7.715075000000001 7.715075000000001 7.715075000000001 ZT8-11 24.1391 24.1391 24.1391 ZT12-15 0 0 0 ZT16-19 23.24025 23.24025 23.24025 ZT20-23 23.493000000000002 23.493000000000002 23.493000000000002