condition mean min max ZT0-3 11.21261 11.21261 11.21261 ZT4-7 8.5672095 8.5672095 8.5672095 ZT8-11 9.730042000000001 9.730042000000001 9.730042000000001 ZT12-15 8.574464500000001 8.574464500000001 8.574464500000001 ZT16-19 8.5916745 8.5916745 8.5916745 ZT20-23 8.788862 8.788862 8.788862