condition mean min max ZT0-3 248.480767 248.480767 248.480767 ZT4-7 183.232057 183.232057 183.232057 ZT8-11 186.416282 186.416282 186.416282 ZT12-15 142.765873 142.765873 142.765873 ZT16-19 190.640942 190.640942 190.640942 ZT20-23 179.6720355 179.6720355 179.6720355