condition mean min max ZT0-3 7.820455 7.820455 7.820455 ZT4-7 8.5558905 8.5558905 8.5558905 ZT8-11 9.151517 9.151517 9.151517 ZT12-15 11.536144 11.536144 11.536144 ZT16-19 10.220118 10.220118 10.220118 ZT20-23 14.0692755 14.0692755 14.0692755