condition mean min max ZT0-3 0.863013 0.863013 0.863013 ZT4-7 0.731744 0.731744 0.731744 ZT8-11 0.53276 0.53276 0.53276 ZT12-15 0.8429745 0.8429745 0.8429745 ZT16-19 1.5366300000000002 1.5366300000000002 1.5366300000000002 ZT20-23 1.17307 1.17307 1.17307