condition mean min max ZT0-3 72.164609 72.164609 72.164609 ZT4-7 73.8172785 73.8172785 73.8172785 ZT8-11 69.55101300000001 69.55101300000001 69.55101300000001 ZT12-15 67.04499949999999 67.04499949999999 67.04499949999999 ZT16-19 117.614383 117.614383 117.614383 ZT20-23 78.989371 78.989371 78.989371