condition mean min max ZT0-3 23.2453 23.2453 23.2453 ZT4-7 20.33665 20.33665 20.33665 ZT8-11 21.3973 21.3973 21.3973 ZT12-15 22.35295 22.35295 22.35295 ZT16-19 26.52235 26.52235 26.52235 ZT20-23 23.068399999999997 23.068399999999997 23.068399999999997