condition mean min max ZT0-3 9.5699 9.5699 9.5699 ZT4-7 7.1258099999999995 7.1258099999999995 7.1258099999999995 ZT8-11 6.2923849999999995 6.2923849999999995 6.2923849999999995 ZT12-15 9.357745000000001 9.357745000000001 9.357745000000001 ZT16-19 11.38825 11.38825 11.38825 ZT20-23 10.86015 10.86015 10.86015