condition mean min max ZT0-3 6.71704 6.71704 6.71704 ZT4-7 5.761270000000001 5.761270000000001 5.761270000000001 ZT8-11 4.25031 4.25031 4.25031 ZT12-15 4.7520500000000006 4.7520500000000006 4.7520500000000006 ZT16-19 6.76297 6.76297 6.76297 ZT20-23 6.086343333333334 6.086343333333334 6.086343333333334