condition mean min max ZT0-3 11.643853 11.643853 11.643853 ZT4-7 11.9310825 11.9310825 11.9310825 ZT8-11 11.101737 11.101737 11.101737 ZT12-15 13.5091815 13.5091815 13.5091815 ZT16-19 11.693437500000002 11.693437500000002 11.693437500000002 ZT20-23 13.226669999999999 13.226669999999999 13.226669999999999