condition mean min max ZT0-3 19.25159 19.25159 19.25159 ZT4-7 16.663379 16.663379 16.663379 ZT8-11 15.9384825 15.9384825 15.9384825 ZT12-15 17.4282435 17.4282435 17.4282435 ZT16-19 16.881069 16.881069 16.881069 ZT20-23 15.830337499999999 15.830337499999999 15.830337499999999