condition mean min max ZT0-3 5.5116625 5.109030000000001 5.914295 ZT4-7 5.31154 5.31154 5.31154 ZT8-11 5.221215 5.221215 5.221215 ZT12-15 0 0 0 ZT16-19 7.305085 7.305085 7.305085 ZT20-23 6.02661 6.02661 6.02661