condition mean min max ZT0-3 39.046527 39.046527 39.046527 ZT4-7 43.418578 43.418578 43.418578 ZT8-11 41.7137125 41.7137125 41.7137125 ZT12-15 41.3612825 41.3612825 41.3612825 ZT16-19 53.1939475 53.1939475 53.1939475 ZT20-23 50.979147 50.979147 50.979147