condition mean min max ZT0-3 10.1113025 9.698540000000001 10.524065 ZT4-7 6.102755 6.102755 6.102755 ZT8-11 11.823 11.823 11.823 ZT12-15 0 0 0 ZT16-19 20.65445 20.65445 20.65445 ZT20-23 20.3305 20.3305 20.3305