condition mean min max ZT0-3 5.50621 4.830685 6.46072 ZT4-7 5.322010000000001 5.322010000000001 5.322010000000001 ZT8-11 3.197945 3.197945 3.197945 ZT12-15 4.9843775 4.895165 5.073589999999999 ZT16-19 4.20559 4.20559 4.20559 ZT20-23 5.27943 5.27943 5.27943