condition mean min max ZT0-3 4.18491777 4.18491777 4.18491777 ZT4-7 7.36421 7.36421 7.36421 ZT8-11 4.684355 4.684355 4.684355 ZT12-15 5.43844 5.43844 5.43844 ZT16-19 2.10189 2.10189 2.10189 ZT20-23 4.26481 4.26481 4.26481