condition mean min max ZT0-3 6.693834717 5.176721654 8.21094778 ZT4-7 3.40927118925 3.4008861455 3.4176562329999998 ZT8-11 4.46827444725 3.662340865 5.2742080295000004 ZT12-15 5.257634049 4.756640014 5.758628084 ZT16-19 6.60833473425 6.546496392 6.670173076499999 ZT20-23 6.231512356750001 5.970692118500001 6.492332595000001