condition mean min max ZT0-3 297.310462 297.310462 297.310462 ZT4-7 278.33637 278.33637 278.33637 ZT8-11 288.049013 288.049013 288.049013 ZT12-15 297.61842249999995 297.61842249999995 297.61842249999995 ZT16-19 287.14799300000004 287.14799300000004 287.14799300000004 ZT20-23 231.3404495 231.3404495 231.3404495