condition mean min max ZT0-3 6.658405 6.658405 6.658405 ZT4-7 5.513059999999999 5.513059999999999 5.513059999999999 ZT8-11 5.52468 5.52468 5.52468 ZT12-15 5.0222999999999995 5.0222999999999995 5.0222999999999995 ZT16-19 7.298465 7.298465 7.298465 ZT20-23 6.33323 6.33323 6.33323