condition mean min max ZT0-3 1082.444509 1082.444509 1082.444509 ZT4-7 485.9265125 485.9265125 485.9265125 ZT8-11 283.44037249999997 283.44037249999997 283.44037249999997 ZT12-15 427.7204815 427.7204815 427.7204815 ZT16-19 234.078265 234.078265 234.078265 ZT20-23 248.9283445 248.9283445 248.9283445