condition mean min max ZT0-3 556.300486 556.300486 556.300486 ZT4-7 497.3397095 497.3397095 497.3397095 ZT8-11 436.5156995 436.5156995 436.5156995 ZT12-15 544.0496109999999 544.0496109999999 544.0496109999999 ZT16-19 568.814186 568.814186 568.814186 ZT20-23 628.3766915 628.3766915 628.3766915