condition mean min max ZT0-3 73.618989 73.618989 73.618989 ZT4-7 63.6541285 63.6541285 63.6541285 ZT8-11 64.2665605 64.2665605 64.2665605 ZT12-15 63.440450999999996 63.440450999999996 63.440450999999996 ZT16-19 57.199772 57.199772 57.199772 ZT20-23 54.112241499999996 54.112241499999996 54.112241499999996