condition mean min max ZT0-3 19.685475 19.34585 20.025100000000002 ZT4-7 29.510399999999997 29.510399999999997 29.510399999999997 ZT8-11 31.263399999999997 31.263399999999997 31.263399999999997 ZT12-15 0 0 0 ZT16-19 25.88305 25.88305 25.88305 ZT20-23 22.37075 22.37075 22.37075