condition mean min max ZT0-3 12.063375 11.49615 12.630600000000001 ZT4-7 11.46025 11.46025 11.46025 ZT8-11 12.0944 12.0944 12.0944 ZT12-15 0 0 0 ZT16-19 12.19745 12.19745 12.19745 ZT20-23 12.1186 12.1186 12.1186