condition mean min max ZT0-3 38.086436 38.086436 38.086436 ZT4-7 39.793534 39.793534 39.793534 ZT8-11 50.216247 50.216247 50.216247 ZT12-15 44.1019925 44.1019925 44.1019925 ZT16-19 49.935434 49.935434 49.935434 ZT20-23 48.1556315 48.1556315 48.1556315