condition mean min max ZT0-3 4.485525 4.389305 4.581745 ZT4-7 3.772385 3.772385 3.772385 ZT8-11 4.568725 4.568725 4.568725 ZT12-15 0 0 0 ZT16-19 4.361155 4.361155 4.361155 ZT20-23 4.310485 4.310485 4.310485