condition mean min max ZT0-3 11.300461 11.300461 11.300461 ZT4-7 14.206615 14.206615 14.206615 ZT8-11 13.717474 13.717474 13.717474 ZT12-15 14.0669745 14.0669745 14.0669745 ZT16-19 14.115035500000001 14.115035500000001 14.115035500000001 ZT20-23 13.0890135 13.0890135 13.0890135