condition mean min max ZT0-3 9.230658333333334 5.5834399999999995 12.781500000000001 ZT4-7 6.133335000000001 6.133335000000001 6.133335000000001 ZT8-11 9.79669 9.79669 9.79669 ZT12-15 12.766475 10.695450000000001 14.837499999999999 ZT16-19 13.4417 13.4417 13.4417 ZT20-23 13.015049999999999 13.015049999999999 13.015049999999999