condition mean min max ZT0-3 9.398262500000001 8.3229 10.473625 ZT4-7 6.844405 6.844405 6.844405 ZT8-11 11.4215 11.4215 11.4215 ZT12-15 0 0 0 ZT16-19 22.8994 22.8994 22.8994 ZT20-23 14.4757 14.4757 14.4757