condition mean min max ZT0-3 666.573665 666.573665 666.573665 ZT4-7 629.282464 629.282464 629.282464 ZT8-11 603.3822025 603.3822025 603.3822025 ZT12-15 739.8409035 739.8409035 739.8409035 ZT16-19 814.9886114999999 814.9886114999999 814.9886114999999 ZT20-23 914.2843809999999 914.2843809999999 914.2843809999999