condition mean min max ZT0-3 387.383717 387.383717 387.383717 ZT4-7 487.184044 487.184044 487.184044 ZT8-11 444.752938 444.752938 444.752938 ZT12-15 459.034057 459.034057 459.034057 ZT16-19 366.7622465 366.7622465 366.7622465 ZT20-23 391.586027 391.586027 391.586027