condition mean min max ZT0-3 8.775059 8.775059 8.775059 ZT4-7 10.8525575 10.8525575 10.8525575 ZT8-11 11.4759225 11.4759225 11.4759225 ZT12-15 10.5295105 10.5295105 10.5295105 ZT16-19 8.519465499999999 8.519465499999999 8.519465499999999 ZT20-23 9.147164 9.147164 9.147164