condition mean min max ZT0-3 271.663584 271.663584 271.663584 ZT4-7 186.463801 186.463801 186.463801 ZT8-11 478.2310305 478.2310305 478.2310305 ZT12-15 459.173417 459.173417 459.173417 ZT16-19 556.4144229999999 556.4144229999999 556.4144229999999 ZT20-23 307.438914 307.438914 307.438914