condition mean min max ZT0-3 12.085897 12.085897 12.085897 ZT4-7 12.2887305 12.2887305 12.2887305 ZT8-11 12.62963 12.62963 12.62963 ZT12-15 11.855435499999999 11.855435499999999 11.855435499999999 ZT16-19 13.8643885 13.8643885 13.8643885 ZT20-23 12.525049500000002 12.525049500000002 12.525049500000002