condition mean min max ZT0-3 0.3018295 0.1783345 0.4253245 ZT4-7 0.6096245 0.6096245 0.6096245 ZT8-11 0.4560215 0.4560215 0.4560215 ZT12-15 0 0 0 ZT16-19 0.3513185 0.3513185 0.3513185 ZT20-23 0.5050515 0.5050515 0.5050515