condition mean min max ZT0-3 8.7753075 8.532015000000001 9.0186 ZT4-7 6.856925 6.856925 6.856925 ZT8-11 10.27026 10.27026 10.27026 ZT12-15 0 0 0 ZT16-19 10.97405 10.97405 10.97405 ZT20-23 10.72121 10.72121 10.72121