condition mean min max ZT0-3 115.198489 115.198489 115.198489 ZT4-7 84.5834375 84.5834375 84.5834375 ZT8-11 66.674085 66.674085 66.674085 ZT12-15 85.9020625 85.9020625 85.9020625 ZT16-19 64.29137300000001 64.29137300000001 64.29137300000001 ZT20-23 64.9359675 64.9359675 64.9359675