condition mean min max ZT0-3 968.153611 968.153611 968.153611 ZT4-7 814.500454 814.500454 814.500454 ZT8-11 845.5459185 845.5459185 845.5459185 ZT12-15 1485.166632 1485.166632 1485.166632 ZT16-19 1194.121439 1194.121439 1194.121439 ZT20-23 1586.365949 1586.365949 1586.365949