condition mean min max ZT0-3 206.116374 206.116374 206.116374 ZT4-7 178.92746849999997 178.92746849999997 178.92746849999997 ZT8-11 204.6348715 204.6348715 204.6348715 ZT12-15 173.052214 173.052214 173.052214 ZT16-19 269.86334450000004 269.86334450000004 269.86334450000004 ZT20-23 289.5576245 289.5576245 289.5576245