condition mean min max ZT0-3 6.029125 6.029125 6.029125 ZT4-7 12.04565 12.04565 12.04565 ZT8-11 7.181305 7.181305 7.181305 ZT12-15 7.26389 7.26389 7.26389 ZT16-19 6.628489999999999 6.628489999999999 6.628489999999999 ZT20-23 7.326885000000001 7.326885000000001 7.326885000000001