condition mean min max ZT0-3 2.878415 2.4294450000000003 3.3273849999999996 ZT4-7 2.62331 2.62331 2.62331 ZT8-11 4.12223 4.12223 4.12223 ZT12-15 0 0 0 ZT16-19 4.83957 4.83957 4.83957 ZT20-23 3.79197 3.79197 3.79197