condition mean min max ZT0-3 13.844453 13.844453 13.844453 ZT4-7 11.0338635 11.0338635 11.0338635 ZT8-11 12.3129635 12.3129635 12.3129635 ZT12-15 10.025331999999999 10.025331999999999 10.025331999999999 ZT16-19 9.9706115 9.9706115 9.9706115 ZT20-23 9.937197000000001 9.937197000000001 9.937197000000001