condition mean min max ZT0-3 13.280619 13.280619 13.280619 ZT4-7 16.4678 16.4678 16.4678 ZT8-11 13.904301 13.904301 13.904301 ZT12-15 14.828932 14.828932 14.828932 ZT16-19 14.2856175 14.2856175 14.2856175 ZT20-23 14.960658 14.960658 14.960658