condition mean min max ZT0-3 592.469558 592.469558 592.469558 ZT4-7 619.0329905 619.0329905 619.0329905 ZT8-11 733.760563 733.760563 733.760563 ZT12-15 812.706283 812.706283 812.706283 ZT16-19 674.562694 674.562694 674.562694 ZT20-23 589.94875 589.94875 589.94875