condition mean min max ZT0-3 244.423639 244.423639 244.423639 ZT4-7 140.4137805 140.4137805 140.4137805 ZT8-11 111.675013 111.675013 111.675013 ZT12-15 216.895626 216.895626 216.895626 ZT16-19 207.2320815 207.2320815 207.2320815 ZT20-23 398.2714105 398.2714105 398.2714105