condition mean min max ZT0-3 10.706924 10.706924 10.706924 ZT4-7 10.688026 10.688026 10.688026 ZT8-11 12.046965 12.046965 12.046965 ZT12-15 11.880423 11.880423 11.880423 ZT16-19 11.177392 11.177392 11.177392 ZT20-23 11.220831 11.220831 11.220831