condition mean min max ZT0-3 9.27045 9.27045 9.27045 ZT4-7 5.8141750000000005 5.8141750000000005 5.8141750000000005 ZT8-11 5.259375 5.259375 5.259375 ZT12-15 9.947189999999999 9.947189999999999 9.947189999999999 ZT16-19 12.3604 12.3604 12.3604 ZT20-23 13.8257 13.8257 13.8257