condition mean min max ZT0-3 19.9436 16.01485 23.87235 ZT4-7 29.89815 29.89815 29.89815 ZT8-11 22.3351 22.3351 22.3351 ZT12-15 0 0 0 ZT16-19 34.2446 34.2446 34.2446 ZT20-23 43.99105 43.99105 43.99105