condition mean min max ZT0-3 49.438477 49.438477 49.438477 ZT4-7 54.765441 54.765441 54.765441 ZT8-11 51.006212500000004 51.006212500000004 51.006212500000004 ZT12-15 49.573139999999995 49.573139999999995 49.573139999999995 ZT16-19 38.805941499999996 38.805941499999996 38.805941499999996 ZT20-23 39.5637265 39.5637265 39.5637265