condition mean min max ZT0-3 247.593190975 172.9566597 322.22972225 ZT4-7 542.6566762250001 517.8336851500001 567.4796673000001 ZT8-11 358.9377362 310.04795065 407.82752175 ZT12-15 239.923888125 209.01053635 270.8372399 ZT16-19 626.834701275 540.9347188 712.7346837499999 ZT20-23 754.2971323 694.5472508 814.0470138000001