condition mean min max ZT0-3 36.18235 16.1944 47.0368 ZT4-7 19.79815 19.79815 19.79815 ZT8-11 23.741999999999997 23.741999999999997 23.741999999999997 ZT12-15 38.657 29.0333 48.280699999999996 ZT16-19 51.10165 51.10165 51.10165 ZT20-23 53.7558 53.7558 53.7558