condition mean min max ZT0-3 14.885975 12.89865 16.8733 ZT4-7 4.33847 4.33847 4.33847 ZT8-11 2.60164 2.60164 2.60164 ZT12-15 0 0 0 ZT16-19 4.96235 4.96235 4.96235 ZT20-23 5.8466249999999995 5.8466249999999995 5.8466249999999995