condition mean min max ZT0-3 4.5643275 4.317795 4.81086 ZT4-7 3.93669 3.93669 3.93669 ZT8-11 4.2022949999999994 4.2022949999999994 4.2022949999999994 ZT12-15 0 0 0 ZT16-19 5.90283 5.90283 5.90283 ZT20-23 5.454705000000001 5.454705000000001 5.454705000000001