condition mean min max ZT0-3 7.36489 7.36489 7.36489 ZT4-7 5.71022 5.71022 5.71022 ZT8-11 6.289285 6.289285 6.289285 ZT12-15 6.342155 6.342155 6.342155 ZT16-19 7.769105 7.769105 7.769105 ZT20-23 7.123155 7.123155 7.123155