condition mean min max ZT0-3 9.528565 9.528565 9.528565 ZT4-7 9.5105425 9.5105425 9.5105425 ZT8-11 9.5793 9.5793 9.5793 ZT12-15 9.5508755 9.5508755 9.5508755 ZT16-19 9.0548435 9.0548435 9.0548435 ZT20-23 8.792175499999999 8.792175499999999 8.792175499999999