condition mean min max ZT0-3 134.804827 134.804827 134.804827 ZT4-7 335.4319125 335.4319125 335.4319125 ZT8-11 318.87837149999996 318.87837149999996 318.87837149999996 ZT12-15 388.0675775 388.0675775 388.0675775 ZT16-19 271.3433705 271.3433705 271.3433705 ZT20-23 217.69801999999999 217.69801999999999 217.69801999999999