condition mean min max ZT0-3 258.406307 258.406307 258.406307 ZT4-7 297.72063449999996 297.72063449999996 297.72063449999996 ZT8-11 299.18593350000003 299.18593350000003 299.18593350000003 ZT12-15 322.14687100000003 322.14687100000003 322.14687100000003 ZT16-19 302.503763 302.503763 302.503763 ZT20-23 310.5691365 310.5691365 310.5691365