condition mean min max ZT0-3 11.383135 11.383135 11.383135 ZT4-7 10.1512985 10.1512985 10.1512985 ZT8-11 9.9928085 9.9928085 9.9928085 ZT12-15 11.474010499999999 11.474010499999999 11.474010499999999 ZT16-19 11.7490475 11.7490475 11.7490475 ZT20-23 11.970655 11.970655 11.970655