condition mean min max ZT0-3 8.948263 8.948263 8.948263 ZT4-7 9.592635 9.592635 9.592635 ZT8-11 9.3245665 9.3245665 9.3245665 ZT12-15 9.105436 9.105436 9.105436 ZT16-19 9.6067745 9.6067745 9.6067745 ZT20-23 9.358305999999999 9.358305999999999 9.358305999999999